PRP-108 Performance Standards and Policies for Structural-Use Panels

Transcription

1 A P A S T A N D A R D PRP-108 Performance Standards and Policies for Structural-Use Panels Published by APA The Engineered Wood Association February 1994 A P A The Engineered Wood Association

2 1997 APA THE ENGINEERED WOOD ASSOCIATION ALL RIGHTS RESERVED. ANY COPYING, MODIFICATION, DISTRIBUTION OR OTHER USE OF THIS PUBLICATION OTHER THAN AS EXPRESSLY AUTHORIZED BY APA IS PROHIBITED BY THE U.S. COPYRIGHT LAWS. TABLE OF CONTENTS Page Preface... 1 Definitions... 3 Manufacturing & Performance Standard for APA Rated Sturd-I-Floor Panels General Requirements Identification... 5 Manufacturing & Performance Standard for APA Rated Sheathing Panels General Requirements Identification Manufacturing & Performance Standard for APA Rated Siding Panels General Requirements Identification APA Qualification Policy for Trademarking Privileges for Structural-Use Panels General Qualification Testing for Rated Sheathing and Sturd-I-Floor Qualification Testing for Rated Siding Product Evaluation Reexamination Trademarking APA Quality Assurance Policy for Structural-Use Panels Scope Purpose Mill Quality Control APA Quality Assurance Sampling Testing & Test Requirements Reporting Resampling Intensive Sampling Repeated Intensive Samplings & Trademark Withdrawals Requalification Manual of APA Test Methods for Structural-Use Panels... 32

3 A performance standard is oriented toward the end use of the product and does not prescribe by what means the product will be manufactured. The overall objective is to assure, for a particular end use, that the product will satisfy the requirements of the application for which it is intended. To do this, the performance criteria in the standard must address the critical attributes of the product that will assure successful performance in the marketplace. This necessitated the development of new and innovative test methods, each linked to field requirements. Therefore, under performance testing, the qualification process correlates the attributes of the product to the marketplace. On the quality assurance side, routine tests need only reflect that the product being made is the same product that qualified. An attempt has been made to use quick-response test methods which are sensitive to manufacturing changes. Therefore, in the interest of speed of testing, quality assurance tests were developed and recommended, where necessary, over existing methods which were not responsive to the manufacturing environment. PREFACE 2. Product Evaluation Concurrent with the submission for qualification based on performance, an additional sample from the same manufacturing lot is evaluated for properties (e.g., linear expansion, strength retention) which can be measured on a sustained quality control basis. The test values obtained from the product evaluation are considered to represent the low end of the intended manufacturing range and are taken as control values. A product specification is then written which is specific to the mill and end product under qualification. This individual mill specification becomes the quality control instrument for future production of a product certified to meet a performance standard. Mill specifications are established on the product by its manufacturer, who is responsible for their maintenance. Should conditions change, the manufacturer is free to request a change in the mill specification by requalifying the changed product under the performance-based criteria. 3. Quality Assurance STURD-I-FLOOR STANDARD SHEATHING STANDARD SIDING STANDARD Qualifying under a performance-based standard involves the following steps: 1. Qualification Based on Performance A sample of the product is submitted sufficient for testing under the performance criteria in the standard. Generally these criteria include demonstrations of structural adequacy, stability and durability. The results of these performance-based tests are the basis for product acceptance. The performance standard places minimum constraint on the manufacturing process. Product quality is the responsibility of the mill. Quality and process control is defined by an approved mill procedures manual on file with APA. The mill quality control records developed by the Certified Inspector are audited by APA, and check testing is performed at regular intervals. The quality control tests are sensitive to manufacturing variables. Products falling below the mill specification limit will be considered out of control, with the appropriate trademark withdrawn until control is re-established according to the provisions of the APA Quality Assurance Policy. Performance-based standards provide considerable latitude in manufacturing but carry with them the concurrent responsibility of the manufacturer to produce a uniform product which is, in fact, similar to the product which has passed the performance-based tests. QUALIFICATION POLICY QUALITY ASSURANCE POLICY 1

4 APA PERFORMANCE-RATED PANEL QUALIFICATION AND QUALITY ASSURANCE PROGRAM FOR APA RATED SHEATHING, APA RATED STURD-I-FLOOR & APA RATED SIDING QUALIFICATION SAMPLE RANDOMIZE SAMPLE PERFORMANCE SAMPLE PRODUCT EVALUATION SAMPLE RATED SHEATHING & STURD-I-FLOOR STABILITY S LINEAR EXPANSION BUCKLING DURABILITY S EXPOSURE 1 EXPOSURE 2 STRUCTURAL S UNIFORM LOAD CONCENTRATED LOAD STATIC IMPACT NAIL HOLDING RACKING SHEAR RATED SIDING STABILITY S LINEAR EXPANSION BUCKLING EDGE SWELL EDGE CHECKING SURFACE S SURFACE CHANGE FINISH ADHESION SURFACE REPAIRS OVERLAYS MECHANICAL PROPERTIES PANEL FLEXURE STIFFNESS STRENGTH PANEL PROPERTIES GRADE LINEAR EXPANSION THICKNESS SWELL (Varies with standard and product) DURABILITY BREAKING LOAD 1 CYCLE 6 CYCLE WOOD FAILURE (Varies with standard and product) QUARTERLY SAMPLES WEEKLY SAMPLES DAILY SAMPLES DURABILITY S EXTERIOR PERFORMANCE CRITERIA SATISFIED? YES CERTIFICATION OF SPAN RATING MILL SPECIFICATION CONTROL VALUES ASSIGNED NO RESAMPLE PRODUCT NO PRODUCTION STAFF SATISFIED? YES PRODUCT IN CONTROL? YES ONGOING APA QUALITY ASSURANCE NO LOSS OF APA TRADEMARK PENDING PASSING INTENSIVE SAMPLE FAILING 2 INTENSIVE QUALITY SAMPLING? PASSING

5 DEFINITIONS All-Veneer Panel Generally a conventional plywood panel with alternate layers of veneer running perpendicular to one another. Composite Panel Any panel containing a combination of veneer and wood-based material. Control Value The numerical limit established for the mill specification for a given mechanical or physical property. Exposure 1 Designation of product durability. Products with this designation are intended for protected construction uses where durability to resist moisture exposure due to long construction delays, or other conditions of similar severity, is required. Exposure 2 Designation of product durability. Products with this designation are intended for protected construction uses where moderate delays in providing protection may be expected or conditions of high humidity and water leakage may exist. Exterior Designation of product durability. Products with this designation are suitable for continuous exposure to the weather or moisture. Major Panel Axis The axis placed across supports according to the Span Rating, which is generally the long dimension of a product. Mill Specification The document which indicates certain manufacturing characteristics that contribute to product quality and consistency. The mill specification is unique to each qualified product under a given performance standard. The specification is used in the mill quality control program as audited under the APA Quality Assurance Policy. Nonveneer Panel Any wood-based panel which does not contain veneer (except hardboard siding), consistent with the definition of structural-use panels, including products such as flakeboard, waferboard, oriented strand board and particleboard. Performance Standard A standard for trademarked products based on performance. Performance is measured by tests that approximate end-use conditions. PS 1 Voluntary Product Standard PS 1 for Construction and Industrial Plywood. Qualification Policy APA policy covering procedures by which a mill may obtain performance-standard trademarking privileges. Quality Assurance Policy APA policy covering the third-party auditing of a mill s quality control program. 3 Sample Test material cut from a panel. Sample Mean The average test value, obtained by summing the observations and dividing by the number of tests. Sample Standard Deviation A measure of test variation. Calculated as: S = [Σ x 2 (Σ x) 2 /n] / (n 1) where: S = sample standard deviation x = test observation n = number of observations Span Rating An index number identifying the recommended maximum center-to-center support spacing in inches for the specified end use under normal use conditions. Specimen The individual test piece cut from the sample. Stability A panel s ability to remain flat during normal exposure to weather during construction and while in service. Stability Coefficient A numerical coefficient which is an indication of a siding product s ability to remain flat when installed according to application recommendations. Stability Index A numerical index which is an indication of a sheathing or single-floor panel s ability to remain flat when installed according to application recommendations. Structural-Use Panel A panel product composed primarily of wood (except hardboard siding) which, in its commodity end use, is essentially dependent upon certain mechanical and/or physical properties for successful end-use performance. Such a product carrying an APA trademark shall conform to one or more of the end-use performance standards adopted by APA The Engineered Wood Association and, where applicable, approved by one or more national regulatory agencies for single-layer floors; for sheathing with respect to roofs, subfloors, and walls; for exterior siding; or for concrete forming. Such a product shall be identified in a manner clearly conveying its intended end use. Test Exposure Condition The condition to which a panel is subjected prior to test. Generally, the dry, wet, or wet and then redry conditions. Test Specimen Delamination Any separation along a test specimen edge and/or end.

6 STURD-I-FLOOR STANDARD December 4, GENERAL MANUFACTURING AND PERFORMANCE STANDARD FOR APA RATED STURD-I-FLOOR PANELS 2.3 Structural Performance APA RATED STURD-I-FLOOR is a wood-based, structural-use panel intended for use as combination subfloor and underlayment when fastened to supports spaced in accordance with the Span Rating in inches. This standard covers the raw materials and binding materials, as they affect performance, dimensions, tolerances, and moisture content of APA RATED STURD-I-FLOOR. Included are criteria as measured by standard test procedures to determine compliance through performance. (a) 2.0 REQUIREMENTS 2.1 Raw Materials Wood Veneer. Any wood veneer used as a component of a panel shall be in accordance with the applicable veneer grade, species, and workmanship requirements of the most recent edition of Voluntary Product Standard PS 1. Exception: veneer of other quality may be used in lieu of that required provided the manufacturer defines the quality and demonstrates that its use and his control of its quality will assure adequate performance both during qualification and in routine production Other Material. Other raw material used in panel manufacture shall be produced primarily from wood. 2.2 Panel Construction Panels qualifying for a Span Rating may be identified in three classes: all-veneer panels, composite panels, or nonveneer panels. See Preface for definition of terms. Panels shall qualify on an individual panel construction basis for the end use and Span Rating upon demonstrated conformance to the appropriate requirements of Sections 2.3 through 2.7. Performance shall be as given below when tested for each structural condition in accordance with the referenced standard APA test procedure. APA The Engineered Wood Association Qualification Policy details specimen requirements and retest procedures Concentrated Loads. Panels shall be tested according to the procedures of APA Test Method S-1 (b) for concentrated static and impact loads. Panels shall conform to the criteria of Table 1 for the end use and span shown on the trademark Uniform Loads. Panels shall be tested according to the procedures of APA Test Method S-2 for uniform loads. Panels shall conform to the criteria of Table 2 for the end use and span shown on the trademark Fastener Holding. Panels shall be tested according to the procedures of APA Test Method S-4 for fastener holding under lateral and withdrawal loads. Panels shall conform to the criteria of Table 3 for the end use and thickness shown on the trademark. 2.4 Physical Properties Performance shall be as given below for each physical property when tested in accordance with the referenced APA test method. APA The Engineered Wood Association Qualification Policy details specimen requirements and retest procedures Linear Expansion. Panels shall be tested according to one of the following linear expansion test procedures: Oven Dry to Vacuum-Pressure Soak. Panels shall be tested according to the procedures of APA Test Method P-1 for linear expansion from oven dry to vacuum-pressure soak. The linear expansion shall be no more than 0.50% as measured between the brass eyelets. (a) Publications to provide product end-use information are available from APA The Engineered Wood Association, P.O. Box 11700, Tacoma, WA (b) Methods given in Manual of APA Test Methods for Structural- Use Panels. 4

7 One-Sided Wetting and Relative Humidity. Panels shall be tested according to the procedures of APA Test Method P-2 for linear and thickness expansion as measured by one-sided wetting and P- 3 for linear and thickness expansion as measured by relative humidity exposures. The free panel linear expansion shall be no more than 0.30% along the major panel axis and 0.35% across the major panel axis. Thickness swell shall be 25% or less Full-Scale Testing. Panels shall be tested according to the procedures of APA Test Method P- 4 for linear expansion as measured in a full-scale test assembly. The restrained panel expansion, as measured over the entire assembly, shall be no more than 0.20% along the major panel axis and 0.25% across the major panel axis Stability. Panels shall be evaluated for the stability index according to APA Test Method P-5. The stability index shall be 5.5 or greater for the end use and span shown on the trademark. 2.5 Panel Durability Performance shall be as given below for properties that affect the adhesive bonding system when tested in accordance with the referenced APA test method. APA The Engineered Wood Association Qualification Policy details specimen requirements and retest procedures Bond Durability Exposure 1. Panels composed entirely of veneer and rated as Exposure 1 shall meet the PS- 1 bond requirements for Interior panels bonded with exterior glue. Composite panels which are so rated shall satisfy the delamination requirements of the Qualification Policy when tested in accordance with APA Test Method P-9, following moisture cycling according to APA Test Method D-5. Nonveneer panels and wood-based material for composite panels so rated shall exhibit a minimum average strength retention of 50% with no individual panel retained strength less than 40% when tested in accordance with APA Test Method S-6 following moisture cycling according to APA Test Method D Exposure 2. Panels composed entirely of veneer and rated as Exposure 2 shall meet the PS- 1 bond requirements for Interior panels bonded with intermediate glue. Composite and nonveneer panels which are so rated shall be moisture cycled according to the procedures of APA Test Method D-1. Following moisture cycling, all of the appropriate structural performance criteria provided in Section 2.3 shall be satisfied for the span and end use to be noted on the trademark Mold Resistance. Panels shall satisfy the mold resistance test according to the procedures of APA Test Method D-2 as defined by the Qualification Policy Resistance to Elevated Temperature. Panels satisfy sufficient elevated-temperature resistance (160 F) when they meet the requirements of Section Bacteria Resistance. Panels shall satisfy the bacteria test according to the procedures of APA Test Method D-3 as defined by the Qualification Policy. 2.6 Dimensional Tolerance and Squareness of Panels Size. A tolerance of plus 0, minus 1/8 inch shall be allowed on specified length and/or width Thickness. A tolerance of plus or minus 1/32 inch shall be allowed on the trademark-specified thickness unless otherwise determined through Qualification testing Squareness and Straightness. Panels shall be square within 1/64 inch per lineal foot measured along the diagonals. All panels shall be manufactured so that a straight line drawn from one corner to the adjacent corner is within 1/16 inch of the panel edge. 2.7 Moisture Content Moisture content of panels at time of shipment shall not exceed 18% of oven-dry weight as determined by APA Test Method P IDENTIFICATION All APA RATED STURD-I-FLOOR panels shall be identified with an APA trademark bearing the APA RATED STURD-I-FLOOR designation appropriate under these specifications. The manufactured nominal thickness and Span Rating shall be included in the trademark. Products which carry the APA RATED STURD-I-FLOOR trademark are to be applied in accordance with APA RATED STURD-I-FLOOR application recommendations published by APA The Engineered Wood Association. Any supplemental application recommendation of the manufacturer must be clearly marked on each panel. STURD-I-FLOOR STANDARD 5

8 STURD-I-FLOOR STANDARD TABLE 1. Concentrated Static and Impact Test Performance Criteria for Panels Tested According to APA Test Method S-1. Performance Requirements Minimum Ultimate Load (lb) Maximum Test Deflection Exposure Following (in.) Under Span Rating Conditions (a) Static Impact (c) 200-lb Load (b) 16 Dry Wet/Redry Dry Wet/Redry Dry Wet/Redry Dry Wet/Redry Dry Wet/Redry (a) Wet/redry is exposure to three days continuous wetting followed by testing dry. (b) Criteria applies under static concentrated load and following impact according to APA Test Method S-1. (c) Impact shall be 75 ft-lb for Span Ratings up to 24 oc, 90 ft-lb for 32 oc, and 150 ft-lb for 48 oc. TABLE 2. Uniform Load Performance Criteria for Panels Tested According to APA Test Method S-2. Performance Requirements Minimum Test Average Ultimate Exposure Deflection Uniform Load Span Rating Conditions (a) Under Load (psf) 16 Dry or Wet/Redry at 100 psf Dry or Wet/Redry at 100 psf Dry or Wet/Redry at 100 psf Dry or Wet/Redry at 100 psf Dry or Wet/Redry at 80 psf 225 (a) Wet/redry is exposure to three days continuous wetting followed by testing dry. TABLE 3. Fastener Performance Criteria Under Lateral and Withdrawal Loads for Panels Tested According to APA Test Method S-4. Performance Requirements for Panel Test Minimum Ultimate Load (lb) Thickness Nail Exposure (in.) Size (a) Condition (b) Lateral Withdrawal Through 1/2 6d Dry Greater than 1/2 8d Wet/Redry (a) Common smooth-shank nail. (b) Wet/redry is exposure to three days continuous wetting followed by testing dry. 6

9 MANUFACTURING AND PERFORMANCE STANDARD FOR APA RATED SHEATHING PANELS February 10, GENERAL APA RATED SHEATHING is a wood-based, structural-use panel intended for use in construction applications as sheathing for roofs, subflooring, and walls when fastened to supports spaced in accordance with the Span Rating in inches. APA STRUCTURAL I RATED SHEATHING panels are intended for use where cross-panel strength and stiffness or racking shear properties are of major importance. APA RATED SHEATHING/CEILING DECK panels are intended for use where a surface will be exposed to view and appearance is important. APA RATED WALL BRACING panels are intended for wall applications where bracing is required. This standard covers the raw materials and binding materials, as they affect performance, dimensions, tolerances, and moisture content. Included are criteria as measured by standard test procedures to determine compliance through performance. (a) 2.0 REQUIREMENTS 2.1 Raw Materials Wood Veneer. Any wood veneer used as a component of a panel shall be in accordance with the applicable veneer grade, species, and workmanship requirements of the most recent edition of Voluntary Product Standard PS 1. Exception: Veneer of other quality may be used in lieu of that required provided the manufacturer defines the quality and demonstrates that its use and his control of its quality will assure adequate performance both during qualification and in routine production. For APA RATED SHEATHING/CEILING DECK, veneer grades and workmanship shall conform to Veneer Grade and Workmanship General Requirements, of the APA 303 Siding Manufacturing Specifications. Exception: Veneer of other quality may be used per above for panel back, and inner plies which are not exposed by grooving wider than 3/8 inch, and not adjacent to the face. Any wood veneer used as a component of a STRUC- TURAL I panel shall be in accordance with the applicable veneer grade and workmanship requirements for STRUCTURAL I plywood in the most recent edition of Voluntary Product Standard PS Other Material. Other raw material used in panel manufacture shall be produced primarily from wood. 2.2 Panel Construction Panels may be identified in three classes: all-veneer panels, composite panels, or nonveneer panels. See Preface for definition of terms. Panels shall qualify on an individual panel construction basis for the end use and Span Rating upon demonstrated conformance to the appropriate requirements of Sections 2.3 through Surface Treatment. One surface of APA RATED SHEATHING/CEILING DECK shall have some form of decorative treatment which may be in the form of overlaying, texturing, grooving, embossing, or scratch sanding Panel Edges. APA RATED SHEATHING/CEIL- ING DECK panels shall be tongue-and-grooved on sides in accordance with the APA Manufacturing Specification for Tongue-and-Groove and Shiplap Joints. Exception: other profiles may be used, providing they meet the structural performance requirements of Section Structural Performance Performance shall be as given below when tested for each structural condition in accordance with the referenced standard APA test procedure. APA The Engineered Wood Association Qualification Policy details specimen requirements and retest procedures Concentrated Loads. Panels which are rated for roof span and for subfloor span shall be tested according to the procedures of APA Test Method S-1 (b) for concentrated static and impact loads. Panels shall conform to the criteria of Table 1 for the end use and span shown on the trademark. (a) Publications to provide product end-use information are available from APA The Engineered Wood Association, P.O. Box 11700, Tacoma, WA, (b) Methods given in Manual of APA Test Methods for Structural- Use Panels. SHEATHING STANDARD 7

10 TABLE 1. Concentrated Static and Impact Test Performance Criteria for Panels Tested According to APA Test Method S-1. SHEATHING STANDARD Performance Requirements Minimum Ultimate Load (lb) Maximum Test Deflection End Use Exposure Following (in.) Under Span Rating Conditions (a) Static Impact (d) 200-lb Load (b) Roof 16 Dry Wet (c) Roof 20 Dry Wet (c) Roof 24 Dry Wet (c) Roof 32 Dry Wet (c) Roof 40 Dry Wet (c) Roof 48 Dry Wet (c) Roof 54 Dry Wet (c) Roof 60 Dry Wet (c) Subfloor 16 Dry Wet/Redry Subfloor 20 Dry Wet/Redry Subfloor 24 Dry Wet/Redry Subfloor 32 Dry Wet/Redry Subfloor 48 Dry Wet/Redry (a) (b) (c) (d) Wet/redry is exposure to three days continuous wetting followed by testing dry. Wet conditioning is exposure to three days continuous wetting and tested wet. Criteria apply under static concentrated load according to APA Test Method S-1. They do not apply following impact. Not applicable. Impact shall be 75 ft-lb for Span Ratings up to 24 oc, 90 ft-lb for 32 oc, 120 ft-lb for 40 oc, and 150 ft-lb for 48 oc and greater. TABLE 2. Uniform Load Performance Criteria for Panels Tested According to APA Test Method S-2. Performance Requirements Minimum Test Average Ultimate End Use Exposure Deflection Uniform Span Rating Conditions (b) Under Load Load (psf) Wall 16 Dry (d) 75 (c) Wall 24 Dry (d) 75 (c) Bracing 16 Dry (d) 75 (c) Bracing 24 Dry (d) 75 (c) Roof 16 (a) Dry at 35 psf 150 Roof 20 (a) Dry at 35 psf 150 Roof 24 (a) Dry at 35 psf 150 Roof 32 Dry at 35 psf 150 Roof 40 Dry at 35 psf 150 Roof 48 Dry at 35 psf 150 Roof 54 Dry at 35 psf 150 Roof 60 Dry at 35 psf 150 Subfloor 16 Subfloor 20 Subfloor 24 Subfloor 32 Subfloor 48 Dry at 100 psf 330 Wet/Redry 330 Dry at 100 psf 330 Wet/Redry 330 Dry at 100 psf 330 Wet/Redry 330 Dry at 100 psf 330 Wet/Redry 330 Dry at 80 psf 225 Wet/Redry 225 (a) Panels with Roof 16 and Roof 20 ratings must also meet performance requirements for Wall 16 rating. Panels with Roof 24 rating must also meet requirements for Wall 24 rating. (b) Wet/redry is exposure to three days continuous wetting followed by testing dry. (c) The major panel axis is to be placed along the supports for testing. (d) Not applicable. 8

11 TABLE 3. Racking Load Performance Criteria for Panels Tested According to APA Test Method S-3. Performance Requirements (a) Minimum Nail Spacing Maximum Nominal Test Nail (inches) Test Load Deflection Minimum Ultimate Panel Thickness Exposure Size Panel Intermediate (lb/ft) Test Load Load (lb/ft) (inches) Condition (common) Edge Studs (b) Sheathing Structural I (inches) Sheathing Structural I Less than 5/16 (c) Dry 6d /16 Dry 6d /8 Dry 8d /16 Dry 8d /32 and greater Dry 10d (a) Stud spacing 16 o.c. for Wall 16, Wall 20, Bracing 16, Roof 16 and Roof o.c. for all other Span Ratings and all Structural I panels. (b) For studs spaced 24 o.c., nail spacing on intermediate studs shall be 6 o.c. for panels 7/16 and thinner. (c) Criteria apply to APA RATED WALL BRACING panels of all thicknesses. SHEATHING STANDARD TABLE 4. Fastener Performance Criteria Under Lateral and Withdrawal Loads for Panels Tested According to APA Test Method S-4. Performance Requirements for Panel Test Minimum Ultimate Load (lb) Thickness Exposure End Use (in.) Nail Size (a) Condition (c) Lateral Withdrawal Wall Through 1/2 6d Dry 120 (b) Greater than 1/2 8d Wet/Redry 90 (b) Bracing Through 1/2 6d Dry 120 (b) Greater than 1/2 8d Wet/Redry 90 (b) Roof Through 1/2 6d Dry Greater than 1/2 8d Wet/Redry Subfloor Through 1/2 6d Dry Greater than 1/2 8d Wet/Redry (a) Common smooth-shank nail. (b) Not applicable. (c) Wet/redry is exposure to three days continuous wetting followed by testing dry. TABLE 5. Uniform Load Performance Criteria for APA STRUCTURAL I RATED SHEATHING Panels Tested According to APA Test Method S-2. Performance Requirements Nominal Test Average Min. Ultimate Thickness Exposure Deflection Uniform Load (in.) Conditions Under Load (psf) 7/16 Dry at 20 psf 90 15/32 Dry at 35 psf 135 1/2 Dry at 40 psf /32 & 5/8 Dry at 70 psf /32 & Thicker Dry at 90 psf 300 9

12 SHEATHING STANDARD Panels to be identified STRUCTURAL I and which are 7/16" or thicker shall also be tested according to the procedures of APA Test Method S-1 with the framing members parallel to the strength axis, except the load is applied at mid-panel length. Minimum test panel size is 4x8-foot. The framing shall be spaced 24 inches o.c. The panel ends shall not be supported by framing. Panels shall conform to the criteria of Table 1 for Roof Uniform Loads. Panels shall be tested according to the procedures of APA Test Method S-2 for uniform loads. Panels shall conform to the criteria of Table 2 for the end use and span shown on the trademark. Panels to be identified STRUCTURAL I shall also be tested according to procedures of APA Test Method S-2 with the framing members parallel to the strength axis. Minimum test panel size is 4x8-foot. The framing shall be spaced 24 inches o.c. The panel ends shall not be supported by framing. Panels shall conform to the criteria of Table Wall Racking. Panels which are rated for wall span and for roof span 16, 20 or 24 shall be tested according to the procedures of APA Test Method S-3 for wall racking. Panels shall conform to the criteria of Table 3 for the thickness shown on the trademark. Panels to be identified STRUCTURAL I shall meet the STRUCTURAL I requirements of Table 3 for the thickness shown on the trademark, when tested according to the procedures of APA Test Method S-3. Panels of all thicknesses to be identified APA RATED WALL BRACING shall meet the requirements of Table 3 for panels less than 5/16 inch thick, when tested according to the procedures of APA Test Method S Fastener Holding. Panels shall be tested according to the procedures of APA Test Method S-4 for fastener holding under lateral load. Panels which are rated for roof span and for subfloor span shall also be tested for fastener holding under withdrawal load. Panels shall conform to the criteria of Table 4 for the end use and thickness shown on the trademark. 2.4 Physical Properties Performance shall be as given below for each physical property when tested in accordance with the referenced APA test method. APA The Engineered Wood Association Qualification Policy details specimen requirements and retest procedures Linear Expansion. Panels shall be tested according to one of the following linear expansion test procedures: Oven Dry to Vacuum-Pressure Soak. Panels shall be tested according to the procedures of APA Test Method P-1 for linear expansion from oven dry to vacuum-pressure soak. The linear expansion shall be no more than 0.50% as measured between the brass eyelets One-Sided Wetting and Relative Humidity. Panels shall be tested according to the procedures of APA Test Method P-2 for linear expansion as measured by one-sided wetting and P-3 for linear expansion as measured by relative humidity exposures. The free panel linear expansion shall be no more than 0.30% along the major panel axis and 0.35% across the major panel axis Full-Scale Testing. Panels shall be tested according to the procedures of APA Test Method P-4 for linear expansion as measured in a full-scale test assembly. The restrained panel expansion, as measured over the entire assembly, shall be no more than 0.20% along the major panel axis and 0.25% across the major panel axis Stability. Panels shall be evaluated for the stability index according to APA Test Method P-5. The stability index shall be 5.2 or greater for the end use and span shown on the trademark. 2.5 Panel Durability Performance shall be as given below for properties that affect the adhesive bonding system when tested in accordance with the referenced APA test method. APA The Engineered Wood Association Qualification Policy details specimen requirements and retest procedures Bond Durability Exposure 1. Panels composed entirely of veneer and rated as Exposure 1 shall meet the PS-1 bond requirements for Interior panels bonded with exterior glue. Composite panels which are so rated shall satisfy the delamination requirements of the Qualification Policy when tested in accordance with APA Test Method P-9, following moisture cycling according to APA Test Method D-5. Nonveneer panels and wood-based material for composite panels so rated shall exhibit a minimum average strength retention of 50% with no individual panel retained strength less than 40% when tested in accordance with APA Test Method S-6 following moisture cycling according to APA Test Method D-5. 10

13 Exposure 2. Panels composed entirely of veneer and rated as Exposure 2 shall meet the PS-1 bond requirements for Interior panels bonded with intermediate glue. Composite and nonveneer panels which are so rated shall be moisture cycled according to the procedures of APA Test Method D-1. Following moisture cycling, all of the appropriate structural performance criteria provided in Section 2.3 except shall be satisfied for the span and end use to be noted on the trademark Mold Resistance. Panels shall satisfy the mold resistance test according to the procedures of APA Test Method D-2 as defined by the Qualification Policy Resistance to Elevated Temperature. Panels satisfy sufficient elevated-temperature resistance (160 F) when they meet the requirements of Section Bacteria Resistance. Panels shall satisfy the bacteria test according to the procedures of APA Test Method D-3 as defined by the Qualification Policy. 2.6 Dimensional Tolerance and Squareness of Panels Size. A tolerance of plus 0, minus 1/8 inch shall be allowed on specified length and/or width Thickness. A tolerance of plus or minus 1/32 inch shall be allowed on the trademark-specified thickness unless otherwise determined through Qualification testing Squareness and Straightness. Panels shall be square within 1/64 inch per lineal foot measured along the diagonals. All panels shall be manufactured so that a straight line drawn from one corner to the adjacent corner is within 1/16 inch of the panel edge. 2.7 Moisture Content Moisture content of panels at time of shipment shall not exceed 18% of oven-dry weight as determined by APA Test Method P IDENTIFICATION All APA RATED SHEATHING, APA STRUCTURAL I RATED SHEATHING, APA RATED SHEATHING/ CEILING DECK and APA RATED WALL BRACING panels shall be identified with an APA trademark bearing the APA RATED SHEATHING, APA STRUC- TURAL I RATED SHEATHING, APA RATED SHEATHING/CEILING DECK or APA RATED WALL BRACING designation appropriate under these specifications. The manufactured nominal thickness and the Span Rating shall be included in the trademark. Veneer-faced APA RATED SHEATHING/CEILING DECK panels shall also include in the trademark the appropriate APA 303 Siding face grade classification in accordance with the APA 303 Siding Manufacturing Specifications, without reference to 303. Products which carry the APA RATED SHEATHING, APA STRUCTURAL I RATED SHEATHING, APA RATED SHEATHING/CEILING DECK or APA RATED WALL BRACING trademark are to be applied in accordance with APA RATED SHEATHING, APA STRUCTURAL I RATED SHEATHING, APA RATED SHEATHING/ CEILING DECK or APA RATED WALL BRACING application recommendations published by APA The Engineered Wood Association. Any supplemental application recommendation of the manufacturer must be clearly marked on each panel. SHEATHING STANDARD 11

14 MANUFACTURING AND PERFORMANCE STANDARD FOR APA RATED SIDING PANELS February 7, 1991 SIDING STANDARD 1.0 GENERAL APA RATED SIDING is a wood-based, structural-use panel intended for use in construction application as exterior siding when fastened to supports spaced in accordance with the Span Rating in inches. APA RATED SIDING structural-use panels also include strips which may be cut from such panels by the manufacturer for use as lap siding. This standard covers the raw materials and binding materials, as they affect performance, dimensions, tolerances, and moisture content of APA RATED SIDING. Included are criteria as measured by standard test procedures to determine compliance through performance. (a) 2.0 REQUIREMENTS 2.1 Raw Materials Wood Veneer. Any wood veneer used as a component of a panel shall be in accordance with the applicable veneer grade and workmanship requirements of the most recent edition of APA 303 Siding Manufacturing Specification. Exception: Veneer of other quality may be used in one-step composite panels, provided the manufacturer defines the quality and demonstrates that its use and the control of its quality will assure adequate performance both during qualification and in routine production Other Material. Other raw material used in panel manufacture shall be produced primarily from wood. 2.2 Panel Construction Panels may be identified in three classes: all-veneer panels, composite panels, or nonveneer panels. See Preface for definition of terms. Panels shall qualify on an individual panel construction basis for the Span Rating upon demonstrated conformance to the appropriate requirements of Sections 2.3 through 2.8. Plywood manufactured to the provisions of the most recent edition of APA 303 Siding Manufacturing Specification qualify as APA Rated Siding. 2.3 Structural Performance Performance shall be as given below when tested for each structural condition in accordance with the referenced standard APA test method. APA The Engineered Wood Association Qualification Policy details specimen requirements and retest procedures Concentrated Static Loads. Products shall be tested in accordance with the procedures of APA Test Method S-9 (b) for concentrated static loads. Panel and lap siding products shall conform to the criteria of Table 1 for the span shown on the trademark Uniform Loads. Products shall be tested in accordance with the procedures of APA Test Method S-10 for uniform loads. Panel and lap siding products shall conform to the criteria of Table 2 for the span shown on the trademark Hard-Body Impact Loads. Products shall be tested in accordance with the procedures of APA Test Method S-11 for hard-body impact loads. Panel and lap siding products shall conform to the criteria of Table 3 for the span shown on the trademark Soft-Body Impact Loads. Products shall be tested in accordance with the procedures of APA Test Method S-12 for soft-body impact loads. Panel and lap siding products shall conform to the criteria of Table 4 for the span shown on the trademark Fastener Head Pull-Through. Products shall be tested in accordance with the procedures of APA Test Method S-4 for fastener head pull-through. Panel and lap siding products shall conform to the criteria of Table 5 for span shown on the trademark Wall Racking. Products shall be tested in accordance with the procedures of APA Test Method S-3 for wall racking. Panel siding products shall conform to the criteria of Table 6 for the span shown on the trademark. Lap siding products do not have racking resistance capability and therefore are not tested. (a) Publications to provide product end-use information are available from APA The Engineered Wood Association, P.O. Box 11700, Tacoma, WA, (b) Methods given in Manual of APA Test Methods for Structural- Use Panels. 12

15 TABLE 1. Concentrated Static Load Performance Criteria for Products Tested According to APA Test Method S-9. Performance Requirements Test Maximum Residual Average Residual Minimum Exposure Deflection (in.) Indentation (in.) Ultimate Load Span Rating Conditions After 100-lb Load After 100-lb Load (lb) 16 & 24 Dry & Wet (a) (b) (b) 200 (a) Wet conditioning is exposure to seven days continuous wetting and tested wet. (b) Residual indentation or deflection is measured one minute following load removal. TABLE 2. Uniform Load Performance Criteria for Products Tested According to APA Test Method S-10. Performance Requirements Test Maximum Residual Minimum Exposure Deflection (in.) Ultimate Load Span Rating Conditions After 50-psf Load (psf) 16 & 24 Dry & Wet (a) (b) 150 (a) Wet conditioning is exposure to seven days continuous wetting and tested wet. (b) Residual deflection is measured one minute following load removal. SIDING STANDARD TABLE 3. Hard-Body Impact Load Performance Criteria for Products Tested According to APA Test Method S-11. Performance Requirements Test Average Residual Minimum Exposure Indentation (in.) Ultimate Load Span Rating Conditions After 4-ft-lb Impact (ft-lb) 16 & 24 Dry & Wet (a) (b) 8 (a) Wet conditioning is exposure to seven days continuous wetting and tested wet. (b) Residual indentation is measured one minute following load removal. TABLE 4. Soft-Body Impact Load Performance Criteria for Products Tested According to APA Test Method S-12. Performance Requirements Test Maximum Residual Minimum Exposure Deflection (in.) Ultimate Load Span Rating Conditions After 30-ft-lb Impact (ft-lb) 16 & 24 Dry & Wet (a) (b) 45 (a) Wet conditioning is exposure to seven days continuous wetting and tested wet. (b) Residual deflection is measured one minute following load removal. 13

16 TABLE 5. Fastener Head Pull-Through Criteria for Products Tested According to APA Test Method S-4. Performance Requirements Test Minimum Exposure Ultimate Load Span Rating Conditions Nail Size (b) (ft-lb) 16 & 24 Dry 6d 55 (a) Wet conditioning is exposure to seven days continuous wetting and tested wet. (b) Hot-dipped galvanized casing nail or siding nail. Wet (a) 40 TABLE 6. Racking Load Performance Criteria for Products Tested According to APA Test Method S-3. SIDING STANDARD Nail Spacing Performance Requirements (a) Thickness Maximum Minimum at Point of Nail Panel Intermediate Test Design Deflection Ultimate Nailing Size Edge Studs Exposure Load at Design Load (in.) (box) (in.) (in.) Conditions (lb/ft) (in.) (lb/ft) (c) 6d 6 12 Dry Wet (b) (a) Stud spacing 16 in. o.c. or 24 in. o.c. (b) Wet exposure shall follow the recommended procedures outlined in ASTM E-72. (c) Thickness at point of nailing shall be that at base of grooves (if grooved) unless otherwise recommended by the manufacturer. 2.4 Physical Properties Performance shall be as given below for each physical property when tested in accordance with the referenced APA test method. APA The Engineered Wood Association Qualification Policy details specimen requirements and retest procedures Stability. Panels shall be tested according to one of the following stability test procedures: Stability Coefficient. Panels shall be tested according to the procedures of APA Test Method P-10 for stability coefficient of siding products. The stability coefficient shall be 0.80 or greater Full-Scale Testing. Panels shall be tested according to the procedures of APA Test Method P-11 for stability on a large-scale test frame. The average expansion of the restrained panels, as measured over the entire assembly, shall be less than or equal to 0.20% along either axis of the frame. The five percent exclusion limit of buckling distortions across supports and panel distortions along any support shall be no greater than 0.20 inch as determined by the procedures of Method P Edge Stability. Siding shall be tested according to the following edge stability test procedures: Edge Swell. Panels shall be tested for edge swell according to the procedures of APA Test Method P-2 for dimensional change due to one-sided wetting. The edge thickness swell shall be no greater than 25% after three weeks of wetting exposure Edge Checking. Panels shall be tested according to the procedures of APA Test Method P-12 for edge checking. APA Rated Siding shall satisfy the edge checking requirements of the Qualification Policy. 14

17 2.5 Surface Characteristics Performance shall be as given below for properties that affect finish performance when tested in accordance with the referenced APA test method. APA The Engineered Wood Association Qualification Policy details specimen requirements and retest procedures Surface Texture Change. Specimens shall be tested according to the procedures of APA Test Method F-1. The numerical value for surface change shall be no greater than Finish Adhesion. Specimens shall be tested according to the procedures of APA Test Method F-2. The average numerical value for initial dry adhesion of the standard control finish shall be not less than 2.0 pounds per inch of width, with no specimen being less than 1.5. If adhesion failures occur within the substrate, the product is acceptable, providing that more than 50 percent of the failed area is within the substrate. (Substrate bond durability is evaluated in Section ) Surface Repairs. Specimens with surface repairs shall be tested according to the procedures of APA Test Method F-3. Products shall conform to the criteria of Table 7. Size and type of repair shall be according to the most recent edition of PS Overlays. Specimens with overlays shall be tested according to the procedures of APA Test Method F-4. Products shall conform to the criteria of Table 8 in addition to Sections and TABLE 7. Surface Repair Performance Criteria for Samples Tested According to APA Test Method F-3. Test Exposure Condition Performance Requirements SIDING STANDARD Test 1 Boil-Dry Cycles Probe No cracking, shrinkage, or loss of bond. Power Sawing Repair shall cut cleanly and stay in place. Cut repair is also probed as above. Test 2 Soak-Dry Cycles Probe No cracking, shrinkage, or loss of bond. Power Sawing Repair shall cut cleanly and stay in place. Cut repair is also probed as above. Test 3 Finishability Finish Compatibility Standard control finish shows no signs of incompatibility (e.g. alligatoring, crawling, etc.). Finish Adhesion Requirements of Section shall be satisfied. Test 4 Machinabilitiy The repairs shall machine cleanly and stay in place. TABLE 8. Overlay Performance Criteria for Samples Tested According to APA Test Method F-4. Test Exposure Condition Performance Requirements Test 1 Vacuum-Pressure-Dry Delamination limited to an area 1/2 deep x 1 wide. No internal separation of the overlay. No cracks in the overlay. Test 2 Machinability Performance of the overlay must be at least equivalent to that of the typical PS-1 phenolic Medium Density Overlay. The overlay shall present a smooth edge after the machining tests (sawing, nailing, routing, drilling) and shall not tear, crack, chip or fuzz. Test 3 Finishability Requirements of Section shall be satisfied. 15

18 SIDING STANDARD 2.6 Panel Durability Performance shall be as given below for properties that affect the adhesive bonding system when tested in accordance with the referenced APA test method. APA The Engineered Wood Association Qualification Policy details specimen requirements and retest procedures Bond Durability. Panels composed entirely of veneer shall meet the PS-1 bond requirements for Exterior type. Nonveneer panels, wood-based material for composite panels, and finished (veneered) composite panels shall exhibit a minimum average strength retention of 55% with no individual panel retained strength less than 45% when tested in accordance with the procedures of APA Test Method S-6 following moisture cycling according to the procedures of APA test Method D-5. In addition, at least 95% of composite panel specimens shall pass delamination requirements when tested in accordance with the procedures of APA Test Method P-9, following moisture cycling according to the procedures of APA Test Method D-5 extended to ten (10) moisture cycles Mold Resistance. Panels shall satisfy the mold resistance test according to the procedures of APA Test Method D Resistance to Elevated Temperature. Panels satisfy sufficient elevated-temperature resistance (160 F) when they meet the requirements of Section Bacteria Resistance. Panels shall satisfy the bacteria test according to the procedures of APA Test Method D Dimensional Tolerance and Squareness of Panels Size. A tolerance of plus 0, minus 1/8 inch shall be allowed on specified length and/or width Thickness. A tolerance of plus or minus 1/32 inch shall be allowed on the trademark-specified thickness unless otherwise determined through Qualification testing Squareness and Straightness. Panels shall be square within 1/64 inch per lineal foot measured along the diagonals. All panels shall be manufactured so that a straight line drawn from one corner to the adjacent corner is within 1/16 inch of the panel edge. 2.8 Moisture Content Moisture content of panels at time of shipment shall not exceed 18% of oven-dry weight as determined by APA Test Method P IDENTIFICATION All APA RATED SIDING shall be identified with an APA trademark bearing the APA RATED SIDING designation appropriate under these specifications. The manufactured nominal thickness, EXTERIOR exposure durability classification and the Span Rating shall be included in the trademark. Products which carry the APA RATED SIDING trademark are to be applied in accordance with APA RATED SIDING application recommendations published by APA The Engineered Wood Association. Any supplemental application recommendation of the manufacturer must be clearly marked on each piece. 16

19 APA QUALIFICATION POLICY FOR TRADEMARKING PRIVILEGES FOR STRUCTURAL-USE PANELS June 9, GENERAL Structural-use panels are wood-based panels which qualify for end uses based on performance. Associated with each end use is an APA manufacturing and performance standard which provides criteria. This qualification policy details specimen requirements, conformance criteria, retest options and product evaluation requirements. 1.1 Performance Concept Acceptance of structural-use panel products is based upon performance testing reflecting attributes which are consistent with end-use requirements. Panels should be able to sustain the structural requirements of construction and/or occupancy, maintain bond integrity during normal exposure, and remain relatively stable during expected moisture exposure. Tests to simulate these conditions have been developed or adopted by APA and criteria specified for the appropriate end use. 1.2 Performance Standard Manufacturing and performance standards developed and promulgated by APA which are covered by this policy include: Manufacturing and Performance Standard for APA RATED STURD-I-FLOOR Panels intended for single-layer floor panels. Manufacturing and Performance Standard for APA RATED SHEATHING Panels intended for sheathing for roofs, subfloors, and walls. Manufacturing and Performance Standard for APA RATED SIDING Panels intended for panel and lap wall sidings. The tests and criteria called for in these standards shall be satisfied as described in this policy. Further, each product qualified shall be evaluated as described in Section 4.0 for the purpose of developing a mill specification, to be used in conjunction with the Quality Assurance Policy. Qualification testing will be at the mill s expense. (a) Methods given in Manual of APA Test Methods for Structural- Use Panels. 2.0 QUALIFICATION ING FOR RATED SHEATHING AND STURD-I-FLOOR 2.1 General Qualification tests required will depend upon the end use designated by the manufacturing and performance standard. Required tests and criteria are detailed in the standard. Conformance and retest requirements are given by test in this section. Tests are conducted according to the application recommendations of the standard for which the panel is being qualified, at the support spacing to be shown on the trademark. Any special product modification which enhances performance (i.e. moisturizing or water repellent treatment) shall be noted per Section 4.1. When necessary, retest options are followed if no change is made in the manufacturing process. If a change in panel configuration or processing is made, additional qualification tests, as necessary, shall be performed. 2.2 Structural Performance Concentrated Loads. A minimum of ten tests (specimens taken from at least five panels) for each test exposure condition shall be evaluated for both concentrated static and impact loads according to APA Test Method S-1. (a) Deflection. At least 90% of tests shall deflect no more than the specified maximum. Retest. If no more than two tests in a lot of ten fail to meet the deflection requirements, another lot of ten may be tested for that requirement. If no more than one test fails in this second round of testing, the requirements shall be considered satisfied Ultimate Load. For each lot, 100% of tests shall support the specified minimum ultimate load. Retest. If no more than one test in a lot of ten fails to meet the minimum ultimate load requirement, another lot of ten may be tested for that requirement. If all pass the retest, the requirements shall be considered satisfied. QUALIFICATION POLICY 17

20 QUALIFICATION POLICY Uniform Loads. A minimum of ten tests (specimens taken from at least five panels) for each test exposure condition shall be evaluated for uniformload capacity according to APA Test Method S Deflection. The average deflection shall not be greater than that specified. Retest. If the average deflection is greater than specified, but does not exceed the requirement by 20%, another lot of ten may be tested for that requirement. If the average of the first and second lot taken together does not exceed that specified, the requirement shall be considered satisfied Ultimate Load. For each lot, 100% of tests shall support the specified minimum ultimate load. Retest. If no more than one test in a lot of ten fails to meet the ultimate-load requirement, another lot of ten may be tested for that requirement. If all specimens pass this retest, the requirements shall be considered satisfied Wall Racking. A minimum of two tests shall be evaluated for wall racking according to APA Test Method S Deflection. The average deflection shall not be greater than that specified. Retest. If the average deflection is greater than specified, but does not exceed the requirement by 20%, another wall may be tested for that requirement. If the average of the three walls taken together does not exceed that specified, the requirement shall be considered satisfied Ultimate Load. For each lot, 100% of tests shall support the specified minimum ultimate load. If only two tests are evaluated, then values shall be within 10% of each other. Retest. If the two test ultimates do not agree within 10%, another wall may be tested for that requirement. If the lowest value of the three walls tested exceeds the specified minimum ultimate load, the requirement shall be considered satisfied Fastener Holding. A minimum of twenty tests (specimens taken from at least five panels) for each test exposure condition and property shall be tested for lateral and withdrawal loads according to APA Test Method S-4. Panel thickness shall be as shown on the trademark Ultimate Load. At least 95% of tests shall support the specified minimum ultimate load. Retest. If no more than four tests in a lot of twenty fail to meet the minimum ultimate load requirement, another lot of twenty may be tested for that requirement. If no more than one fails the retest, the requirements shall be considered satisfied. 2.3 Physical Properties Linear Expansion. One of the following linear expansion test methods and associated criteria shall be satisfied as noted in the appropriate standard. Any special feature included by the manufacturer, such as coatings or moisture conditioning, shall be noted per Section Exposure to Oven Dry and Vacuum- Pressure Soak. A minimum of ten tests (specimens taken from at least five panels) both along and across the major panel axis shall be conducted according to APA Test Method P-1 for linear expansion measured from oven dry to vacuum-pressure soak. At least 80% of specimens from each panel axis shall exhibit a maximum linear expansion, as measured between the brass eyelets from oven dry to soak, no more than specified. Retest. If no more than four tests in a lot of ten fail to meet the maximum linear-expansion requirements for a given panel axis, another lot of ten may be tested for that requirement. If no more than two fail in this second round of testing, the requirement shall be considered satisfied Exposure to One-Sided Wetting and Relative Humidity. A minimum of ten tests (specimens taken from at least five panels) for both along and across the major panel axis shall be conducted according to APA Test Method P-2 for linear and/or thickness expansion measured from as-is to wet-oneside exposure. A minimum of ten tests (specimens taken from at least five panels) for both along and across the major panel axis shall be conducted according to APA Test Method P-3 for linear and/or thickness expansion measured when exposed to relative humidity change. At least 80% of tests from each panel direction and test method shall exhibit a linear expansion no greater than specified. Retest. If no more than four tests in a lot of ten fail to meet the maximum linear-expansion requirements for a given panel axis and test exposure condition, another lot of ten may be tested for that requirement. If no more than two fail in this second round of testing, the requirement shall be considered satisfied. 18

21 Full-Scale Testing. A full-scale test deck is constructed using eight panels according to APA Test Method P-4. The average expansion of the restrained panels, as measured over the entire assembly, shall be less than or equal to that specified Stability. A minimum of ten tests (specimens taken from at least five panels) both along and across the major panel axis shall be conducted to determine the panel s stability index according to the procedures of APA Test Method P-5. At least 80% of tests from each panel direction shall exhibit a minimum stability index no less than the requirement for the span and application. Retest. If no more than four tests in a lot of ten fail to meet the stability requirements, another lot of ten may be tested for that requirement. If no more than two fail in this second round, the requirement shall be considered satisfied. 2.4 Durability Performance Bond Durability Exposure 1. Panels composed of veneer and rated as Exposure 1 shall satisfy the PS-1 bond requirements for Interior panels bonded with exterior glue. Composite panels which are so rated shall have one sample from each of at least twenty panels tested according to APA Test Method D-5 and evaluated for delamination according to APA Test Method P-9 following the fourth and sixth moisture cycles. At least 95% of specimens shall pass four cycles and 90% shall pass six moisture cycles. Nonveneer panels and woodbased material for composite panels which are so rated shall have one sample from each of at least twenty panels cycled according to APA Test Method D-5 and tested for strength retention according to APA Test Method S-6. Strength retention is calculated by the following method: Samples tested shall exhibit the specified minimum strength retention following six moisture cycles. (b) Retest. For composite and nonveneer panels, if the twenty-panel average strength retention meets the requirements but no more than one panel fails to meet the minimum individual panel strength retention specified, another lot of twenty panels may be tested. For composite panels, if more than 85% but fewer than 90% of specimens pass delamination requirements following six cycles of APA Test Method D-5 evaluated according to APA Test Method P-9 (probe test), another lot of twenty panels may be tested. If the retest meets the requirements, bond durability requirements shall be considered satisfied Exposure 2. Panels composed of veneer and rated as Exposure 2 shall satisfy the PS-1 bond requirements for Interior panels bonded with intermediate glue. Composite and nonveneer panels which are so rated shall be moisture cycled according to the procedures of APA Test Method D-1. Structural tests detailed by the standard shall be evaluated according to the performance requirements of Section Mold Resistance. Four panels shall be tested according to the procedures of APA Test Method D Panels composed entirely of veneer are considered to have satisfactory mold resistance if each test group over the twenty-week period shows an average glueline shearing load of at least 90% of the control. In addition, no more than two groups may rate less than 80% and no single group may rate less than 75% Other panels are considered to have satisfactory mold resistance if no test group average is less than the control sample mean less 1.8 times the control sample standard deviation Resistance to Elevated Temperature. Panels satisfying the moisture-cycling requirements of Section shall be considered to have satisfactory resistance to elevated temperature. QUALIFICATION POLICY % RS = P t x 100 P c where: % RS= Percent retained strength of sample P t = Average sample (five-specimen) breaking load after cycling. P c * = Average unexposed sample (fivespecimen) breaking load. *Control specimens are broken in the as-received condition. (b) Because of the extreme severity of the six-cycle test, the strength retention requirement relates to bond durability and does not relate to structural design Bacteria Resistance. At least four panels shall be tested according to the procedures of APA Test Method D Panels composed entirely of veneer are considered to have bacteria resistance if each test group over the twelve-week test shows an average load of at least 80% of the control. No single group may rate below 70% of the control Other panels are considered to have satisfactory bacteria resistance if no test group average is less than the control sample mean less 1.8 times the control sample standard deviation.

22 QUALIFICATION POLICY 3.0 QUALIFICATION ING FOR RATED SIDING 3.1 General Required tests and criteria are detailed in the APA Rated Siding Standard. Conformance and retest requirements are given by test in this section. Tests are conducted according to the application recommendations of the APA Rated Siding Standard, at the support spacing to be shown on the trademark. Any special product modification which enhances performance, such as moisturizing or water repellent treatment, shall be noted per Section 4.1. When necessary, retest options are followed if no change is made in the manufacturing process. If a change in panel configuration or processing is made, additional qualification tests, as necessary, shall be performed. 3.2 Structural Performance Concentrated Loads. A minimum of three tests (specimens taken from at least three panels) for each test exposure condition shall be evaluated for concentrated static and impact loads according to APA Test Methods S-9, S-11, and S Residual Deflection. For each lot, 100% of the tests shall exhibit residual deflections no more than the specified maximum. Retest. If no more than one test in a lot of three fails to meet the residual deflection requirements, another lot of three may be tested for that requirement. If all pass the retest, the requirements shall be considered satisfied Residual Indentation. The average residual indentation shall not be greater than that specified. Retest. If the average residual indentation is greater than specified, but does not exceed the requirement by 20%, another lot of three may be tested for that requirement. If the average of the first and second lot taken together does not exceed that specified, the requirement shall be considered satisfied Ultimate Load. For each lot, 100% of tests shall support the specified minimum ultimate load. Retest. If no more than one test in a lot of three fails to meet the minimum ultimate requirement, another lot of three may be tested for that requirement. If all pass the retest, the requirements shall be considered satisfied Uniform Loads. A minimum of three tests (specimens taken from at least three panels) for each test exposure condition shall be evaluated for uniform load capacity according to APA Test Method S Residual Deflection. For each lot, 100% of the tests shall exhibit residual deflections no more than the specified maximum. Retest. If no more than one test in a lot of three fails to meet the minimum ultimate requirement, another lot of three may be tested for that requirement. If all pass the retest, the requirements shall be considered satisfied Ultimate Load. For each lot, 100% of tests shall support the specified minimum ultimate load. Retest. If no more than one test in a lot of three fails to meet the minimum ultimate requirement, another lot of three may be tested for that requirement. If all pass the retest, the requirements shall be considered satisfied Wall Racking. A minimum of two tests for each test exposure condition shall be evaluated for wall racking according to APA Test Method S Deflection. The average deflection shall not be greater than that specified. Retest. If the average deflection is greater than specified, but does not exceed the requirement by 20%, another wall may be tested for that requirement. If the average of the three walls taken together does not exceed that specified, the requirement shall be considered satisfied Ultimate Load. For each lot, 100% of tests shall support the specified minimum ultimate load. If only two tests are evaluated, then values shall be within 10% of each other. Retest. If the two ultimates do not agree within 10%, another wall may be tested for that requirement. If the lowest value of the three walls tested exceeds the specified minimum ultimate load, the requirement shall be considered satisfied. 20

23 3.2.4 Fastener Head Pull-Through. A minimum of fifteen tests (specimens taken from at least three panels) for each test exposure condition shall be tested for fastener head pull-through according to APA Test Method S-4. Thickness of the panel shall be that at base of grooves (if grooved) unless otherwise recommended by the manufacturer Ultimate Load. At least 85% of tests shall support the specified minimum ultimate load. Retest. If no more than three tests in a lot of fifteen fail to meet the minimum ultimate load requirement, another lot of fifteen may be tested for that requirement. If no more than one fails the retest, the requirements shall be considered satisfied. 3.3 Physical Properties Stability. One of the following stability test methods and associated criteria shall be satisfied as noted in the APA Rated Siding Standard. Any special feature included by the manufacturer, such as coatings or moisture conditioning, shall be noted per Section Stability Coefficient. A minimum of ten tests (specimens taken from at least five panels) both along and across the major panel axis shall be conducted to determine the panel s stability coefficient according to the procedures of APA Test Method P-10. At least 70% of tests from each panel direction shall exhibit a minimum stability coefficient no less than that specified. Retest. If no more than four tests in a lot of ten fail to meet the stability requirements, another lot of ten may be tested for that requirement. If no more than three fail in this second round, the requirement shall be considered satisfied Full-Scale Testing. A large-scale test wall shall be constructed according to APA Test Method P-11. The average panel expansion, as measured over the entire assembly, shall be less than or equal to that specified. The upper five percent exclusion limit of buckling distortions across the supports and panel distortions along any support shall be no greater than that specified Edge Swell and Edge Checking. The following test methods and associated criteria shall be satisfied as noted in the APA Rated Siding Standard. Any special feature included by the manufacturer, such as coatings or moisture conditioning, shall be noted per Section Edge Swell. A minimum of ten tests (specimens taken from at least five panels) shall be conducted according to APA Test Method P-2 for edge swell after three weeks one-sided wetting. At least 80% of specimens shall exhibit a maximum thickness swell no more than specified. Retest. If no more than three tests in a lot of ten fail to meet the maximum edge swell requirement, another lot of ten may be tested for that requirement. If no more than two fail in this second round of testing, the requirement shall be considered satisfied Edge Checking. A minimum of ten tests (specimens taken from at least five panels) shall be conducted according to APA Test Method P-12 for edge checking. At least 90% of the specimens shall exhibit no edge checks. Retest. If no more than two tests in a lot of ten fail to meet the edge checking requirement, another lot of ten may be tested for that requirement. If no more than one test fails in this second round of testing, the requirement shall be considered satisfied. 3.4 Surface Characteristics Surface Change. A minimum of nine tests (three specimens taken from at least three panels) shall be evaluated for surface change according to APA Test Method F No more than one test shall develop surface change values greater than those specified. Retest. If no more than two tests in a lot of nine develop surface change values greater than that specified, another lot of nine may be tested for that requirement. If eight tests pass in this second round of testing, the requirement shall be considered satisfied Finish Adhesion. A minimum of ten tests (two specimens taken from at least five panels) shall be evaluated for finish adhesion according to APA Test Method F For each lot, 100% of the tests shall develop adhesion values no smaller than those specified. Retest. If the average load is at least 90% of that specified and if no more than one test is below the minimum value specified, another lot of ten may be tested for that requirement. If the average of the first and second lots taken together meets the requirement and no value in the second lot falls below that specified, the requirement shall be considered satisfied. QUALIFICATION POLICY 21

24 QUALIFICATION POLICY Surface Repairs. A minimum of five samples, each containing a surface repair of the maximum size intended for the product, shall be evaluated in each of the tests outlined in APA Test Method F Boil-Dry Cycles. For each lot, 100% of the tests shall meet the criteria outlined in Table 7 of the APA Rated Siding Standard. Retest. If no more than one test in a lot of five fails to meet the test requirement, another lot of five may be tested for that requirement. If all specimens pass the retest, the requirements shall be considered satisfied Soak-Dry Cycles. For each lot, 100% of the tests shall meet the criteria outlined in Table 7 of the APA Rated Siding Standard. Retest. If no more than one test in a lot of five fails to meet the test requirement, another lot of five may be tested for that requirement. If all specimens pass the retest, the requirements shall be considered satisfied Finishability. Requirements of Section shall be satisfied Machinability. For each lot, 100% of the tests shall meet the criteria outlined in Table 7 of the APA Rated Siding Standard. Retest. If no more than one test in a lot of five fails to meet the test requirements, another lot of five may be tested for that requirement. If all specimens pass the retest, the requirements shall be considered satisfied Overlays. A minimum of five tests (one specimen taken from at least five panels) shall be evaluated in each of the tests outlined in APA Test Method F Durability Vacuum-Soak-Dry Cycles. For each lot, 100% of tests shall meet the criteria outlined in Table 8 of the APA Rated Siding Standard. Retest. If no more than one test in a lot of five fails to meet the test requirements, another lot of five may be tested for that requirement. If all specimens pass the retest, the requirements shall be considered satisfied Finishability. Requirements of Section shall be satisfied Machinability. For each lot, 100% of tests shall meet the criteria outlined in Table 8 of the APA Rated Siding Standard. Retest. If no more than one test in a lot of five fails to meet the test requirement, another lot of five may be tested for that requirement. If all specimens pass the test, the requirement shall be considered satisfied. 3.5 Panel Durability Bond Durability. Panels composed entirely of veneer shall satisfy the PS-1 bond requirements for Exterior type. Nonveneer panels, wood-based material for composite panels, and finished (veneered) composite panels shall have one sample from each of at least twenty panels cycled according to APA Test Method D-5 and tested for strength retention according to APA Test Method S-6. Strength retention is calculated by the following method: % RS = P t x 100 P c where: %RS = Percent retained strength of sample P t = Average sample (five-specimen) breaking load after cycling. P c * = Average unexposed sample (fivespecimen) breaking load. *Control specimens are broken in the as-received condition. Samples tested shall exhibit the specified minimum average and individual panel strength retention following six moisture cycles. (See footnote b.) In addition, composite panels shall meet the delamination requirements specified following exposure to APA Test Method D-5 extended to ten cycles. Retest. For composite and nonveneer panels, if the twenty-panel average strength retention meets the requirements but no more than one panel fails to meet the minimum individual panel strength retention specified, another lot of twenty panels may be tested. For composite panels, if more than 90% but fewer than 95% of specimens pass delamination requirements, another lot of twenty panels may be tested. If the retest meets requirements, bond durability requirements shall be considered satisfied Mold Resistance. Four panels shall be tested according to the procedures of APA Test Method D Panels composed entirely of veneer are considered to have satisfactory mold resistance if each test group over the twenty-week period shows an average glueline shearing load of at least 90% of the control. In addition, no more than two groups may rate less than 80% and no single group may rate less than 75%. 22

25 Other panels are considered to have satisfactory mold resistance if no test group average is less than the control sample mean less 1.8 times the control sample standard deviation Resistance to Elevated Temperature. Panels satisfying the moisture-cycling requirements of Section shall be considered to have satisfactory resistance to elevated temperature Bacteria Resistance. At least four panels shall be tested according to the procedures of APA Test Method D Panels composed entirely of veneer are considered to have satisfactory bacteria resistance if each test group over the twelve-week test shows an average load of at least 80% of the control. No single group may rate below 70% of the control Other panels are considered to have satisfactory bacteria resistance if no test group average is less than the control sample mean less 1.8 times the control sample standard deviation. 4.0 PRODUCT EVALUATION 4.1 Mill Specification Upon satisfactory completion of the appropriate paragraphs of Section 2.0 or 3.0, a manufacturing specification unique to the product and mill will be written based on product evaluation under this section. This specification will be used in conjunction with the APA Quality Assurance Policy. Product evaluation will be made on the same lot supplied by the manufacturer for qualification testing. Control values (see definition) established during product evaluation will be the basis for quality evaluation of future production by both the individual mill quality control procedures and by the APA Quality Assurance program. Besides the panel characteristics specifically evaluated in this section, any unique manufacturing technique which influences product qualification will be included in the individual mill manufacturing specification. This would include special coatings; heat, water or chemical treatments; overlays; additives; or other manufacturing-related activities. A specification will be developed describing manufacturing characteristics monitored in quarterly reexamination under Section 5.2 and under the APA Quality Assurance Policy. Modification of this specification at mill request is covered under Section Panel Construction All-Veneer Panels. Panels shall be defined as to species and veneer construction for the mill specification and evaluated under Sections 4.3 and 4.4 but excluding Section Composite Panels. Wood-based material shall be evaluated as required in Sections 4.3, and 4.5. In addition, the finished (veneered) panel shall be evaluated by the provisions of Sections 4.3, 4.4.1, and 4.5. Composite panels evaluated for APA Rated Siding are also subject to provisions of Section Nonveneer Panels. Nonveneer panels shall be evaluated under the provisions of Sections 4.3, 4.4 and Mechanical Properties Bending Stiffness. Twenty tests (specimens taken from at least ten panels) shall be evaluated for bending stiffness both along and across the major panel axis according to the procedures of APA Test Method S-5. Control values for each panel direction will be the sample mean and the minimum will be the lower value of a 90% confidence interval established on the mean Bending Strength. Ten tests (specimens taken from at least ten different panels) shall be evaluated for maximum bending moment both along and across the major panel axis according to the procedures of APA Test Method S-5. Control value for each panel direction will be the minimum observed value, or the sample mean less 1.8 times the sample standard deviation, whichever is the higher value. 4.4 Physical Properties Panel Thickness. Finished panel thickness will be evaluated on each of twenty panels by the procedures of APA Test Method P-7. The control value will be the observed minimum individual panel average. The trademark shall carry the minimum nominal fractional thickness rounded up to the nearest 1/32 inch Moisture Content. Panel moisture content will be measured on one specimen from each of twenty panels according to APA Test Method P-6. The control value will be the maximum panel moisture content. A control value will be established only if necessary under linear expansion performance testing per Section Linear Expansion. Linear expansion shall be evaluated for specimens taken from twenty panels by the procedures of APA Test Method P-1. For composite QUALIFICATION POLICY 23

26 QUALIFICATION POLICY panels and for nonveneer panels containing nonoriented furnish, one specimen 3 x 12 shall be prepared perpendicular to the major panel axis only from each panel to be tested. For nonveneer panels containing oriented furnish, one 3 x 12 specimen parallel and one perpendicular to the major panel axis shall be prepared from each panel to be tested. (Nonoriented nonveneer lap siding panels shall be tested parallel to the major panel axis.) The control value will be the highest observed value, or the sample average plus 1.8 times the sample standard deviation, whichever is the lower value. When nonveneer panels contain oriented furnish, separate parallel and perpendicular control values shall be determined Thickness Swell. For APA Rated Siding panels, thickness swell shall be evaluated for specimens taken from twenty panels by the procedures of APA Test Method P-1. The control value for thickness swell at the panel edge will be the highest observed specimen average, or the sample average plus 1.8 times the sample standard deviation, whichever is the lower value. 4.5 Adhesive Bond Properties Moisture-Cycled Breaking Load. For Exposure 1 and Exposure 2, a minimum of twenty samples, one taken from each of twenty panels, shall be moisture cycled according to the procedures of APA Test Method D-4 (single cycle soak-dry test) using specimens described in APA Test Method S-6. For Exposure 1 and Siding, a minimum of twenty samples, one taken from each of twenty panels, shall be moisture cycled according to the procedures of APA Test Method D-5 (Six-Cycle Test) using specimens described in APA Test Method S-6. Immediately following moisture cycling, any panels containing veneer are examined for delamination of veneer-to-veneer or veneer to other wood-based materials according to APA Test Method P-9. At least 95% of the specimens tested shall exhibit no delamination, as defined in Test Method P-9. Moisturecycled samples are then tested according to the procedures of APA Test Method S-6. The individual panel control value for each qualification will be the lowest observed breaking load (five-specimen average), or the sample average less 1.8 times the sample standard deviation, whichever is the higher value. In addition, for Exposure 1 panels tested according to APA Test Methods D-4 and S-6, and for siding panels tested according to APA Test Methods D-5 and S-6, the lower 90% confidence interval will be established on the qualification mean. 5.0 REEXAMINATION 5.1 Quality Assurance An approved mill quality control manual shall be maintained on file with APA The Engineered Wood Association detailing the day-to-day quality control activities of the qualified mill for products other than PS-1 plywood. In addition, compliance to the APA Quality Assurance Policy for Structural-Use Panels will be required. 5.2 Quarterly Reexamination by APA A product qualified and trademarked under this policy shall be subjected to quarterly reexamination. No less than ten panels, collected at a rate not to exceed two per week and one per shift, shall be tested according to the procedures of Sections and Exception: Panels composed entirely of veneer shall be reexamined once every four quarterly cycles Failure to meet established control values shall result in an immediate intensive resampling of current production, which will be tested for the failing property. This resampling shall consist of twenty panels selected and shipped to the APA laboratory by the APA Quality Auditor When results of the resampling fail to meet the applicable test requirements, a requalification for structural properties under Sections and 2.2.2, or and shall be required. 5.3 Change in Mill Specification Any or all control limits of the mill specification may be changed, at mill request, by product evaluation testing, so long as such a product change is demonstrated to be satisfactory with regard to standard and qualification criteria. Such requalification evaluation will be at the mill s expense. 6.0 TRADEMARKING Upon successful completion of qualification testing for the appropriate end-use criteria, APA trademarks will be issued bearing the end-use application recommendations. Continued trademarking approval shall be contingent upon compliance with APA quality assurance requirements as provided in APA Quality Assurance Policy for Structural-Use Panels. 24

27 APA QUALITY ASSURANCE POLICY FOR STRUCTURAL-USE PANELS June 9, SCOPE This policy is intended for use with panel production which has qualified for performance-based trademarking, undergone product evaluation, and for which a Mill Specification and a Mill Quality Control Manual have been written as set forth in the APA Qualification Policy. 2.0 PURPOSE The purpose of this policy is to assure product quality by detecting changes in panel properties which may adversely affect panel performance. In all cases, the criteria to which panels are tested will be the Mill Specification. 3.0 MILL QUALITY CONTROL 3.1 General Maintenance of product quality through day-to-day product evaluation is a mill responsibility. These duties shall be performed by a Certified Inspector on the payroll of the mill, trained and certified by APA to perform quality-related functions. 3.2 Daily Quality Control (Mill Conducted) The Certified Inspector shall perform the quality control activities described in the approved Mill Quality Control Manual (see Qualification Policy, Section 5.1). The Quality Control Manual shall specify product evaluation methods and frequency to be undertaken by the Certified Inspector. Records of these activities shall be available for examination by the APA Quality Auditor. 3.3 Weekly Sampling for Tests Conducted by APA The Certified Inspector shall select and ship the majority of the weekly samples as provided in Section APA QUALITY ASSURANCE 4.1 General APA shall act as a third-party auditing agency, confirming mill quality activities and performing periodic quality checks. 4.2 Auditing Audit. An APA Quality Auditor shall make random unannounced visits to the mill for the purpose of auditing the mill quality control records. During these visits, he shall select samples for APA testing (see Section 5.3) and shall perform other qualityrelated duties as appropriate Other Quality-Related Duties Grade. The APA Quality Auditor shall grade in accordance with the Mill Specification and the sections of the APA Grading Policies applicable to the product involved Panel Size. The APA Quality Auditor shall randomly select a minimum of five panels and examine the length, width, squareness and straightness for conformance to the appropriate specifications Panel Thickness. The APA Quality Auditor shall perform thickness tolerance checks in accordance with the appropriate specifications and the APA Grading Policies Tongue and Groove. The APA Quality Auditor shall examine a minimum of five tongue-andgroove panels for conformance to the appropriate specification, when produced Quarterly Reexamination. The APA Quality Auditor shall select the panels for quarterly reexamination as provided in Section 5.2 of the APA Qualification Policy. The panels shall be shipped to the designated APA laboratory for testing. 4.3 Testing and Reporting APA shall be responsible for testing and reporting test results to the mill as outlined in Sections 6.0 and 7.0. QUALITY ASSURANCE POLICY 25

28 QUALITY ASSURANCE POLICY 5.0 SAMPLING 5.1 General The provisions of this Section apply only to those panels destined for testing by APA as a check on product quality and mill quality control procedures. (Panels for a mill s daily quality testing shall be selected as specified in the Mill Quality Control Manual [see Qualification Policy, Section 5.1].) 5.2 Quotas All-Veneer Products. Products composed wholly of veneer shall be sampled in accordance with provisions of the current APA Adhesive Policy: Rated Sheathing and Rated Sturd-I-Floor as shown for Interior construction grades, and Rated Siding as shown for Exterior-type panels Composite Products Finished Composite. The finished (veneered) product shall be sampled in accordance with provisions of the APA Adhesive Policy: Rated Sheathing and Rated Sturd-I-Floor as shown for Interior construction grades, and Rated Siding as shown for Exterior-type panels Wood-Based Material. Wood-based material destined for use in composite products shall be sampled at the plant producing the finished composite at the rate of one panel of wood-based material for each four panels of finished composite sampled (see Section for finished composite quota). If the plant producing the wood-based material elects the Certified Inspector program with in-plant testing, sampling will occur at this plant at the rate of one panel per day (but not fewer than five panels per week). In such case, no sampling of the wood-based material shall be required at the plant producing the finished composite Nonveneer Products. For these products, the minimum weekly rate of panel selection for testing by the APA laboratory shall be as shown in the following table. Selection shall be in accordance with the provisions of Section 5.3. Weekly Sampling Rate for Nonveneer Panels Weekly Production Weekly Sampling Rate (Million Sq. Ft. 3/8 Basis) (No. of Panels to be Sampled) Up to per 65 M produced 1.3 to samples plus 1 per 175 M over 1.3 Over samples plus 1 per 435 M over 4.8 Note 1: No less than one sample shall be taken during each 8 hours of production regardless of weekly production level except as provided below (Note 2). Note 2: The weekly sampling rate specified in the table and in Note 1 may be reduced by 50% for the following week whenever the plant has no Resampling (Section 8.0) or Intensive Sampling (Section 9.0) notification outstanding or in process in any thickness during the current calendar week. Notification of reduced sampling shall be made by the APA laboratory on the Friday preceding the week for which it applies. 5.3 Panel Selection For all-veneer and composite products, the APA Auditor shall select approximately 20% of the weekly samples during his visit. For nonveneer products, the APA Auditor shall select the panels from the shift(s) during which he makes his visit. The balance of the sampling quota shall be selected by the Certified Inspector. Panels shall be randomly selected assuring, insofar as possible, that consecutively sampled panels originate from different locations in the press. When wood-based material destined for use in composite products is sampled at the mill producing the finished composite, samples shall be selected at the layup line prior to veneering. 5.4 Shipping From each panel selected, a sample shall be cut and shipped to the designated APA testing laboratory together with pertinent sampling information within 24 hours of sample selection, except that allowance shall be made for normal hot-stacking periods and weekends. Failure to ship within the specified time shall result in withdrawal of the right to use APA trademarks. 6.0 ING AND REQUIREMENTS 6.1 Durability All-Veneer Products 26

29 Exposure 1. All-veneer products rated as Exposure 1 shall be tested in accordance with the current APA Adhesive Policy and shall meet the adhesive bond requirements of that Policy for Interior with exterior glue and of the appropriate section of Voluntary Product Standard PS Exposure 2. All-veneer products rated as Exposure 2 shall be tested in accordance with the current APA Adhesive Policy and shall meet the adhesive bond requirements of that Policy for Interior with intermediate glue and of the appropriate section of Voluntary Product Standard PS Rated Siding. All-veneer products rated as APA Rated Siding shall be tested in accordance with the curent APA Adhesive Policy and shall meet the adhesive bond requirements of that Policy for Exterior Siding and those for Exterior type of Voluntary Product Standard PS Composite Products Exposure Composite products rated as Exposure 1 shall be tested in accordance with APA Test Method D-5 (Six-Cycle Test) and evaluated for delamination according to provisions of APA Test Method P-9 (Probe Test for Delamination). (See also Section ) Test Requirements. The last 100 specimens (20 samples) tested shall meet the following requirements: 1. 95% must pass 4 cycles % must pass 6 cycles Composite products rated as Exposure 1 shall further be tested in accordance with APA Test Methods D-4 (Single Cycle Vacuum-Soak-Dry Test), S-6 (Bending Test), and P-9 (Probe Test for Delamination). Test Requirements. 1. The value of each sample is the average breaking load of five specimens. If the average value of the last 20 samples tested is equal to or greater than the lower 90% confidence interval established on the qualification mean, no more than four of the 20 sample values may fall below the control value given in the Mill Specification. If the average value of the last 20 samples tested falls below the lower 90% confidence interval established on the qualification mean, no more than one out of the 20 sample values may fall below the control value given in the Mill Specification. 2. No more than five of the last 100 specimens (20 samples) tested shall exhibit delamination in veneer-to-veneer or veneer-to-wood-basedmaterial gluelines only Composite products rated as Exposure 1 which comprise an Intensive Sampling (Section 9.0), for failure to meet the Single-Cycle Vacuum-Soak-Dry minimum breaking load requirement, shall be tested in accordance with APA Test Methods D-5 (Six-Cycle Test), S-6 (Bending Test) and P-9 (Probe Test for Delamination). Test Requirements. 1. No more than one sample (five-specimen) average breaking load from the 20 panels comprising the Intensive Sampling shall fall below the minimum given in the Mill Specification. 2. No more than ten of the 100 specimens comprising the Intensive Sampling shall exhibit delamination in veneer-to-veneer or veneer-towood-based-material gluelines only Exposure 2. Composite products rated as Exposure 2 shall be tested in accordance with the procedures of APA Test Methods D-4 (Single Cycle Vacuum-Soak-Dry Test), S-6 (Bending Test) and P-9 (Probe Test for Delamination). Test Requirements. 1. The value of each sample is the average breaking load of five specimens. If the average value of the last 20 samples tested is equal to or greater than the lower 90% confidence interval established on the qualification mean, no more than four of the 20 sample values may fall below the control value given in the Mill Specification. If the average value of the last 20 samples tested falls below the lower 90% confidence interval established on the qualification mean, no more than one out of the 20 sample values may fall below the control value given in the Mill Specification. 2. No more than five of the last 100 specimens (20 samples) tested shall exhibit delamination in veneer-to-veneer or veneer-to-wood-based-material gluelines only Rated Siding Composite products rated as APA Rated Siding shall be tested in accordance with APA Test Methods D-5 (Six-Cycle Test), S-6 (Bending Test), and P-9 (Probe Test for Delamination). QUALITY ASSURANCE POLICY 27

30 QUALITY ASSURANCE POLICY Test Requirements. 1. The value of each sample is the average breaking load of five specimens. If the average value of the last 20 samples tested is equal to or greater than the lower 90% confidence interval established on the qualification mean, no more than four of the 20 sample values may fall below the control value given in the Mill Specification. If the average value of the last 20 samples tested falls below the lower 90% confidence interval established on the qualification mean, no more than one out of the 20 sample values may fall below the control value given in the Mill Specification. 2. No more than five of the last 100 specimens (20 samples) tested shall exhibit delamination in veneer-to-veneer or veneer-to-wood-based-material gluelines only Composite products rated as APA Rated Siding shall further be tested in accordance with APA Test Method D-5 extended to 10 cycles using the test specimens described in APA Test Method S-6. Specimens shall then be tested according to APA Test Method P-9 (Probe Test for Delamination). No more than five of the last 100 specimens (20 samples) tested shall exhibit delamination in veneer-to-veneer or veneer-to-wood-based-material gluelines only Composite products rated as APA Rated Siding which comprise an Intensive Sampling (Section 9.0), for failure to meet the Six-Cycle Vacuum-Soak-Dry minimum breaking load requirements, shall be tested in accordance with APA Test Methods D-5 (Six-Cycle Test), S-6 (Bending Test) and P-9 (Probe Test for Delamination). Test Requirements. 1. No more than one sample (five-specimen) average breaking load from the 20 panels comprising the Intensive Sampling shall fall below the minimum given in the Mill Specification. 2. No more than five of the 100 specimens comprising the Intensive Sampling shall exhibit delamination in veneer-to-veneer or veneer-towood-based-material gluelines only Wood-Based Material for Composite Products. When the wood-based material is sampled at the plant producing the material (see Section ), each sample shipped shall be tested for durability according to the provisions of Section When the wood-based material is sampled at the plant producing the finished composite, no durability testing shall be performed on this unveneered material Nonveneer Products Exposure Products which are entirely nonveneer, and wood-based material for composite panels (where applicable), which are rated as Exposure 1, shall be tested in accordance with APA Test Methods D-4 (Single Cycle Vacuum-Soak-Dry Test) and S-6 (Bending Test). Test Requirements. 1. The value of each sample is the average breaking load of five specimens. If the average value of the last 20 samples tested is equal to or greater than the lower 90% confidence interval established on the qualification mean, no more than four of the 20 sample values may fall below the control value given in the Mill Specification. If the average value of the last 20 samples tested falls below the lower 90% confidence interval established on the qualification mean, no more than one out of the 20 sample values may fall below the control value given in the Mill Specification. 2. In the case of panels containing oriented furnish, this requirement shall be applied separately to specimens cut parallel and perpendicular to the major panel axis Panels which comprise an Intensive Sampling (Section 9.0) shall be tested in accordance with APA Test Methods D-5 (Six-Cycle Test) and S-6 (Bending Test). Test Requirements. 1. No more than one sample (five-specimen) average breaking load from the 20 samples comprising the Intensive Sampling shall fall below the minimum given in the Mill Specification. 2. In the case of panels containing oriented furnish, this requirement shall be applied separately to specimens cut parallel and perpendicular to the major panel axis Exposure 2. Products which are entirely nonveneer and which are rated as Exposure 2 shall be tested in accordance with the procedures of APA Test Methods D-4 (Single Cycle Vacuum-Soak-Dry Test) and S-6 (Bending Test). 28

31 Test Requirements. 1. The value of each sample is the average breaking load of five specimens. If the average value of the last 20 samples tested is equal to or greater than the lower 90% confidence interval established on the qualification mean, no more than four of the 20 sample values may fall below the control value given in the Mill Specification. If the average value of the last 20 samples tested falls below the lower 90% confidence interval established on the qualification mean, no more than one out of the 20 sample values may fall below the control value given in the Mill Specification. 2. In the case of panels containing oriented furnish, this requirement shall be applied separately to specimens cut parallel and perpendicular to the major panel axis Rated Siding Products which are entirely nonveneer, and wood-based material for composite panels (where applicable), which are rated as APA Rated Siding, shall be tested in accordance with APA Test Methods D-5 (Six-Cycle Test) and S-6 (Bending Test). Test Requirements. 1. The value of each sample is the average breaking load of five specimens. If the average value of the last 20 samples tested is equal to or greater than the lower 90% confidence interval established on the qualification mean, no more than four of the 20 sample values may fall below the control value given in the Mill Specification. If the average value of the last 20 samples tested falls below the lower 90% confidence interval established on the qualification mean, no more than one out of the 20 sample values may fall below the control value given in the Mill Specification. 2. In the case of panels containing oriented furnish, this requirement shall be applied separately to specimens cut parallel and perpendicular to the major panel axis Panels which comprise an Intensive Sampling (Section 9.0) shall be tested in accordance with APA Test Methods D-5 (Six-Cycle Test) and S-6 (Bending Test). Test Requirements. 1. No more than one sample (five-specimen) average breaking load from the 20 samples comprising the Intensive Sampling shall fall below the minimum given in the Mill Specification. 2. In the case of panels containing oriented furnish, this requirement shall be applied separately to specimens cut parallel and perpendicular to the major panel axis. 6.2 Linear Expansion All-Veneer Products. All-veneer products manufactured to meet all requirements of the most recent edition of Voluntary Product Standard PS 1 need not be tested for linear expansion. Other all-veneer products shall be tested for linear expansion according to provisions of Section Composite Products. Ten percent of the samples shipped per week for durability testing, but not fewer than two per week per thickness shipped, shall be tested for linear expansion perpendicular to the grain of the face veneer following procedures in APA Test Method P-1 (Linear Expansion). Specimen size shall be 3 inches by 12 inches and samples shall be distributed as evenly as possible throughout the week. Test Requirements. No more than four of the last twenty specimens tested shall exceed the maximum value for linear expansion given in the Mill Specification Wood-Based Material for Composite Products. Linear expansion testing is not required on unveneered wood-based material destined for use in composites Nonveneer Products. Ten percent of the samples shipped per week for durability testing, but not fewer than two per week per thickness shipped, shall be tested for linear expansion following procedures in APA Test Method P-1 (Linear Expansion). Specimens from panels which do not contain oriented furnish shall be cut perpendicular to the major panel axis only, except that specimens from lap siding shall be cut parallel to the major panel axis only. In the case of panels containing oriented furnish, one specimen shall be cut parallel and one perpendicular to the major panel axis. Specimen size shall be 3 inches by 12 inches and samples shall be distributed as evenly as possible throughout the week. QUALITY ASSURANCE POLICY 29

32 Test Requirements. No more than four of the last twenty specimens tested shall exceed the maximum value for linear expansion given in the Mill Specification. In the case of panels containing oriented furnish, the requirements shall apply separately to specimens parallel and perpendicular to the major panel axis. 6.3 Thickness Swell Thickness swell is not evaluated for Rated Sheathing or Rated Sturd-I-Floor Rated Siding Thickness swell testing is not required on allveneer products or on wood-based material for composite products. For composite and nonveneer products rated as APA Rated Siding, all samples subjected to linear expansion testing shall also be evaluated for thickness swell using the test specimens and procedures of APA Test Method P-1. Test Requirements. No more than four of the last twenty specimens tested shall exceed the maximum value for thickness swell given in the Mill Specification. 7.0 REPORTING 7.2 The Association shall maintain records of each mill s Specification and conformance to that Specification. Separate records shall be kept for each APA trademarked product. 8.0 RESAMPLING When a mill s record fails to meet any of the requirements listed in Section 6.0, a resampling shall immediately be taken from current production and tested for the delinquent property. This resampling shall consist of twenty samples selected and shipped to the APA laboratory by the Certified Inspector following the procedures of Sections 5.3 and 5.4. (See Section 8.3.) 8.1 When test results of the resampling indicate conformance with the applicable test requirements in Section 6.0, sampling shall revert to the level described in Section When test results of the resampling fail to meet test requirements in Section 6.0, an Intensive Sampling as described in Section 9.0 shall be taken. 8.3 Should failure to meet test requirements on the same property occur for a second time within three weeks of the first such notification, an Intensive Sampling as described in Section 9.0 shall be taken. 7.1 Results shall be communicated to mills as soon as possible upon completion of tests. QUALITY ASSURANCE POLICY 30

33 9.0 INTENSIVE SAMPLING An Intensive Sampling shall consist of twenty samples selected from the first production run of the thickness in question following notification. The Intensive Sampling samples shall be selected and shipped by the APA Quality Auditor according to Sections 5.3 and 5.4 and shall be tested for the delinquent property by the APA laboratory. 9.1 When results of the Intensive Sampling indicate conformance with the applicable test requirements in Section 6.0, sampling shall revert to the level described in Section When results of the Intensive Sampling fail to meet the applicable test requirements in Section 6.0, the right to use Association trademarks for the delinquent product shall be withdrawn. Following withdrawal, the right to use Association trademarks will be reinstated upon completion of a passing Intensive Sampling REPEATED INTENSIVE SAMPLINGS AND TRADEMARK WITHDRAWALS 10.1 Should three Intensive Samplings occur within any sixty-day period, the right to use Association trademarks shall be withdrawn. A single passing Intensive Sampling shall be required for reinstatement Should a second trademark withdrawal occur within three months of the first withdrawal, two passing Intensive Samplings taken on consecutive days shall be required for reinstatement Should a third trademark withdrawal occur within six months of the first, Requalification (Section 11.0) shall be required for reinstatement REQUALIFICATION At any time, any or all the control limits in the Mill Specification may be changed at mill request by requalification as provided in Section 5.3 of the APA Qualification Policy. QUALITY ASSURANCE POLICY 31

34 MANUAL OF APA FOR STRUCTURAL-USE PANELS GENERAL This manual provides specific test methods and procedures as referenced by APA Standards or Policies. Where possible, ASTM and/or ANSI standard procedures are referenced with any deviations from these procedures noted. Series Number Durability Series TABLE OF CONTENTS Page D-1 Moisture Cycle for Performance Testing 33 D-2 Mold Test D-3 Bacteria Test D-4 Moisture Cycle for Quality Assurance D-5 Moisture Cycle for Delamination D-6 Moisture Cycle Shear Test for Quality Assurance Structural/Mechanical Series S-1 Sheathing and Sturd-I-Floor Performance Under Concentrated Static and Impact Loads S-2 Sheathing and Sturd-I-Floor Performance Under Uniform Loads S-3 Wall Performance Under Racking Loads S-4 Fastener-Holding Performance S-5 Panel Bending S-6 Small Specimen Bending for Quality Assurance S-7 Internal Bond S-8 Torque Test S-9 Siding Performance Under Concentrated Static Loads S-10 Siding Performance Under Uniform Loads S-11 Siding Performance Under Hard-Body Impact Loads S-12 Siding Performance Under Soft-Body Impact Loads S-13 Panel Compression S-14 Small Specimen Static Bending Physical Series P-1 Linear Expansion and Thickness Swell Measured from Oven Dry to Vacuum-Pressure-Soak P-2 Linear Expansion and Thickness Swell Measured After Wetting on One Side 52 P-3 Linear and Thickness Expansion Measured by Exposure to Relative Humidity P-4 Linear Expansion Measured in a Full- Scale Frame P-5 Panel Stability Index for Sheathing and Sturd-I-Floor P-6 Panel Moisture Content P-7 Panel Thickness P-8 Panel Density P-9 Probe Test for Delamination P-10 Panel Stability Coefficient for Siding P-11 Buckling Performance Measured on a Large-Scale Wall P-12 Probe Test for Edge Checking of Siding Surface Characteristics Series F-1 Surface Change Measured After Soak-Dry Cycles F-2 Finish Adhesion on Wood-Based Siding F-3 Surface Repair Performance in Wood- Based Siding F-4 Overlay Performance on Wood-Based Siding

35 APA METHOD D-1 MOISTURE CYCLE FOR PERFORMANCE ING March 11, 1980 General This accelerated moisture test cycle is intended as a measure of panel durability and approximates twelve months outdoor exposure. Following the moisture cycle, structural performance tests are generally performed and results compared to performance criteria. Specimen Preparation Specimen dimensions and number required depend upon the performance test to be performed following exposure. Test Procedure The weight of at least two specimens from each lot to be moisture cycled is determined to within ± 0.2%. The specimens are placed in a rack so as to provide maximum exposure to moisture and drying. The specimens are submerged in water and maintained at 150 ± 5 F for 8 hours. Following hot-water soaking, specimens are dried at 180 ± 10 F until panels are within 5% of their original, as-received weight. Specimens are ready for performance testing when dry weight is achieved and following one-half hour cooling in ambient air. APA METHOD D-2 MOLD March 11, 1980 General This test procedure is based on United States Forest Products Laboratory Bulletin No. 1344, Procedures for Measuring the Mold Resistance of Protein Glues. Equipment Cabinets are used to house test specimens under mold producing conditions. Each cabinet is divided into three interconnecting compartments with adjustable specimen trays, each with a sealed door in the front. On each side of the trays toweling is suspended vertically with the lower ends in a water pan acting as wicking in order to provide maximum wet surface area. These pans rest on the floor of the mold cabinet under each compartment. The water level in these pans is kept 2-1/2 to 3 inches in depth. In order to maintain a uniform temperature within the mold cabinets, a walk-in housing surrounds the cabinets. The temperature within this housing is maintained to 80 F with a 500-watt heater controlled by a thermostat. Fan-forced air circulation sufficient to avoid stratification insures even temperature in all areas of the housing. No air circulation is used within the mold cabinets since mold growth is dependent upon still air. Maintenance of a uniform temperature in the housing around the cabinets is essential in order to avoid condensation inside mold cabinets and resulting wet spots. 33

36 Specimen Preparation Test specimens to be used for determination of mold resistance of the adhesive agent in the panel shall depend on the construction of the panels being tested. Panels consisting of all veneer shall be tested by preparing plywood shear specimens as described in PS 1-95, Section , kerfed to pull lathe checks closed for maximum breaking load. Test specimens for testing veneered composite panels and nonveneer panels shall be 1 inch by 5 inches in dimension. Veneered composite panel specimens shall be cut with the veneer grain in the 5-inch direction. Nonveneer panels shall be cut with the 5-inch dimension parallel to the major panel axis, except in the case of panels containing oriented furnish, in which case two complete sets of specimens as described below shall be prepared, one set parallel and one set perpendicular to the major panel axis. The four panels to be mold tested are cut into 100 pairs of specimens (two sets of 100 pairs each in the case of oriented furnish). These paired specimens (mold test specimen and adjacent control specimen) are completely randomized and assembled into 10 groups of 20 specimens each for each direction tested (10 test specimens and 10 controls). The controls and test specimens for each group are then separated. Test Procedure Prior to placing all-veneer specimens in the mold cabinet, they and their controls are stickered, given a fivesecond dip in tap water at room temperature, and then conditioned for one week at 90 to 97% relative humidity and a temperature of 80 F in a separate conditioning chamber. After one week, test and control specimens are removed. Test specimens are dusted with soybean flour and placed flat on green pine sapwood veneer strips that have been stored in the mold cabinet. A stack of these veneer strips and test specimens is then placed in the mold cabinet. The control specimens are allowed to dry at room conditions. At two-week intervals, the designated mold groupings are removed from the cabinet and allowed to dry at room conditions for one week. Test specimens and corresponding control specimens are then tested as required. Ten of these groups are sufficient to test mold-resistance properties of all-veneer products. Mold test specimens for veneered composites and nonveneer products shall be subjected to the five-second dip in tap water and the one-week exposure to 90 to 97% relative humidity and a temperature of 80 F in a separate humidity chamber. Control test specimens from veneered composites and nonveneer products shall be subjected to APA Test Method D-4. At two-week intervals, veneered composites and nonveneer products from the mold test and moisture-cycled control specimens shall be dried at room conditions for one week and then tested according to APA Test Method S-6. 34

37 APA METHOD D-3 BACTERIA March 11, 1980 General This method determines if an adhesive system possesses sufficient resistance to bacterial attack to retain bond integrity under conditions which would promote bacterial growth. Specimen Preparation Test specimen size depends on panel construction. All-veneer panels use shear specimens described in Section of PS 1-95, kerfed to pull lathe checks closed for maximum breaking load. Other panels use a specimen 1 inch by 5 inches. Veneer-containing panels shall be cut with the 5-inch dimension parallel to the grain. The veneer shall be completely free of defects. Specimens from nonveneer panels shall be cut parallel to the major panel axis, except for panels containing oriented furnish, in which case two complete sets of specimens will be cut, one parallel and one perpendicular to the major panel axis. Sufficient material is needed to provide 80 specimens per set as required. Specimens within each set are numbered consecutively 1 through 80 as cut, with odd-numbered specimens destined for bacteria exposure and the adjacent even-numbered specimens destined for control. Ten odd-numbered specimens and their matching ten even-numbered specimens then comprise an exposure group and control for that group. Four such groups are made up from the 80 specimens for each direction tested. Test Procedure Specimens consisting only of veneer, including the controls, are subjected to one-half hour vacuum and one-half hour pressure under tap water following the cycle used in the PS-1 vacuum-pressure test for Exterior plywood. Control specimens are then tested as required in the wet condition. The breaking load is recorded and control averages are determined for each of the exposure groups. For veneered composites and nonveneer products, all specimens are subjected to the vacuum-soak portion of the moisture cycle test of APA Test Method D-4. Control specimens are dried according to the drying provisions of D-4 and broken dry according to the procedures of APA Test Method S-6 with the breaking load recorded and control averages determined for each of the exposure groups. All specimens designated for the bacteria exposure are floated flat in a slurry of soybean flour, water and alder sawdust consisting of 7% soybean flour, 83% water and 10% alder sawdust (sawdust at 18% moisture content). To this slurry is added 0.3% by weight of a 50% solution of sodium hydroxide. The slurry is poured into trays, filling them to a depth of one inch. (NOTE: DO NOT USE COPPER TRAYS.) These trays containing slurry and specimens are then placed into a cabinet described and maintained according to APA Test Method D-2. One exposure group is removed from the cabinet every three weeks over the twelve-week period of the test. All-veneer specimens are tested wet according to the standard plywood shear test method. Specimens of veneered-composite and nonveneer products are dried according to the drying cycle of APA Test Method D-4 and broken according to APA Test Method S-6. 35

38 APA METHOD D-4 MOISTURE CYCLE FOR QUALITY ASSURANCE (Single Cycle Test) March 11, 1980 General This moisture cycle test is a quality control method to accelerate bond degradation. Following moisture cycling a mechanical test is generally performed. Specimen Preparation Specimen s size and configuration depend upon the test to follow moisture cycling. Test Procedure The specimens are placed in racks to insure free movement of water and air around the specimens. The specimens are then placed in a vacuum-pressure vessel which is then filled with 150 F water. A vacuum of 15 inches of mercury is drawn on the vessel for 30 minutes. The vacuum is released and the specimens are allowed to soak in the water at atmospheric pressure for 30 minutes. The vessel is then drained and the specimens dried for 15 hours at 180 F in an oven with fan-forced air circulation of 45 to 50 air changes per minute. The specimens are then tested dry according to the appropriate test method. APA METHOD D-5 MOISTURE CYCLE FOR DELAMINATION AND STRENGTH RETENTION (Six-Cycle Test) May 20, 1986 General This moisture cycle is used in evaluation of delamination and strength retention of products rated as Exposure 1 and Siding. Specimen Preparation Specimen s size and configuration depend on the test to follow moisture cycling. Test Procedure Specimens are placed in a rack such that they will remain separated throughout testing to insure proper drying. The racks are then placed in a pressure vessel and completely submerged in 150 F water. A vacuum of 15 inches of mercury shall be drawn, maintained for 30 minutes and released. Specimens shall then be allowed to soak in the same water at atmospheric pressure for 30 minutes with no additional heating. They shall afterwards be removed and dried for six hours at 180 F in an oven with fan-forced air circulation of 45 to 50 air changes per minute. Specimens shall then be returned to the pressure vessel and the vacuum-soak cycle repeated. Following the second vacuum-soak cycle, specimens shall again be placed in the oven and dried 15 hours. This completes two cycles. Testing shall be continued for two additional days until six cycles have been completed. The specimens are then tested dry according to the appropriate test method. 36

39 APA METHOD D-6 MOISTURE CYCLE SHEAR FOR QUALITY ASSURANCE March 11, 1980 General This moisture cycle shear test is a quality control method to accelerate bond degradation in an allveneer product. Following the moisture cycling, a plywood shear test is conducted on each shear specimen. Specimen Preparation Shear test specimens are prepared as described in Section and shown in Figure 1 of Voluntary Product Standard PS Test Procedure Vacuum-Soak Test. The specimens shall be placed in a vacuum-pressure vessel and submerged in water at 120 F. A vacuum of 15 inches of mercury shall be drawn and maintained for 30 minutes. Following the release of the vacuum, specimens shall continue soaking for 15 hours at atmospheric pressure. The temperature of the water shall not drop below 75 F at any time during the 15 hour soaking period. Specimens shall then be removed from the vessel and tested while wet by tension loading to failure in a shear testing machine operated at a maximum head travel of 16 inches per minute. Jaws of the machine shall securely grip the specimen so there is no slippage. The percentage of wood failure of the specimens shall be determined with specimens in the dry condition and shall be evaluated as described in Section of Voluntary Product Standard PS APA METHOD S-1 SHEATHING AND STURD-I-FLOOR PERFORMANCE UNDER CONCENTRATED STATIC AND IMPACT LOADS August 12, 1980 General The general provisions of the most recent edition of ASTM E-661 are followed. Specimen Preparation Test specimens are specified in ASTM E-661, with the number required given in the Qualification Policy. Specimens may also be moisture cycled as required. Concentrated Impact. Procedures of ASTM E-661 Method A are followed, except: 1) The test frame may be of steel rather than lumber, using fasteners which simulate nails. 2) For Span Ratings greater than 24 oc, the shot bag shall weigh 60 pounds. Test Procedure Concentrated Static. Procedures of ASTM E-661, are followed, except the test frame may be of steel rather than lumber using fasteners which simulate nails. The loading rate is to be 100 pounds per thirty seconds to yield failure within 5 minutes if a hand-pumped hydraulic loading system is used. The width of individual pieces in assembling a test shall be 24 inches for Span Ratings up to 24 oc, and 48 inches for greater Span Ratings. 37

40 APA METHOD S-2 SHEATHING AND STURD-I-FLOOR PERFORMANCE UNDER UNIFORM LOADS March 11, 1980 General This method covers a procedure for determining the performance of structural-use panels under uniform loads such as snow, wind and occupancy loads. The uniform load is applied by atmospheric pressure as a vacuum is drawn under the test specimen which is mounted on fully supported framing members in a vacuum chamber. Equipment Vacuum Chamber. (Figure 1) The vacuum chamber consists of a sealed box with the panel to be tested forming the top. A 6-mil polyethylene sheet or equivalent, the perimeter of which is attached securely with tape, seals the top surface of the vacuum chamber. The chamber must be strong and rigid to resist the applied load without failure or excessive deformation. A vacuum pump is used to reduce the air pressure under the specimen. The load is measured with absolute pressure gages for electronic data readout, but manometers or vacuum gages could also be used. Joist Supports. The framing members are supported so as to resist deflection or rotation under applied load. Deflection Gages. The deflection gages are mounted to rigid tripods whose legs rest above the joists. Deflection is measured to the nearest inch. Specimen Preparation Samples are selected that are representative of the product being tested. Length. The specimen length perpendicular to the framing member is equal to twice the center-to-center spacing. Width. The specimen width is at least 23-1/2 inches. Thickness. The specimen thickness is measured after conditioning and recorded. FIGURE 1. Vacuum Chamber Test Equipment To vacuum pump To pressure gage or manometer Framing member Test panel Polyethylene sheet taped to top of chamber Test panel Tape Framing member, supported to resist rotation and deflection Vacuum chamber 38

41 Conditioning. Prior to testing, the specimen may be subjected to conditioning as specified in ASTM E-661. Test Procedure After conditioning, the specimen to be tested is mounted to the framing members in the vacuum chamber following the anticipated joist spacing and the recommended nail size and spacing. The top of the vacuum chamber is then sealed with the polyethylene sheet, and the tripod holding the deflection gages set in its proper position with the gages positioned to read deflection at the point of maximum deflection (a) of the two outer spans (Figure 2). The panel shall be loaded at a uniform rate of 50 pounds per square foot per minute recording deflections at 25 pounds per square foot increments until maximum load is achieved or until the desired proof load is achieved, as required. Deflection data is required only in sufficient numbers to develop the straight line portion of the load-deflection curve. In no case should the number of data points be less than six. Deflection at a given load is determined by translating the slope to pass through the origin, thereby correcting for any settling of the system. (a) The point of maximum deflection for a uniformly-loaded two-span system occurs at (S) measured from the centerline of the outer joist, where S equals the center-to-center joist spacing. FIGURE 2. Uniform-Load Test Specimens W W/2 d S Framing member supported to resist rotation and vertical movement S = Center-to-center support spacing. d = (s) for two span. W = Panel width, minimum = = Location of deflection measurement. 39

42 APA METHOD S-3 WALL PERFORMANCE UNDER RACKING LOADS May 20, 1986 General The general provisions of Sections 14 and 15 of ASTM E-72 for wall racking are followed. Specimen Preparation Test specimens are prepared as in ASTM E-72 except that the 4 x 4-inch timber attached to the upper plate is reinforced with a 4 x 6-inch steel tube to prevent excessive deformation. An additional dial gage is positioned in the lower right corner of the wall (Fig. 8, ASTM E-72) to record crushing of the lower plate. Stud framing is Douglas fir or southern pine stud grade, with a moisture content 15% or less. Nail size and spacing is as specified in Table 3 of the APA Rated Sheathing Performance Standard and Table 6 of the APA Rated Siding Standard. When 10d nails are used, nominal 3-inch-wide framing shall be used for the center stud (at panel joint) to prevent splitting of framing member. Cleaned scaffold nails can be used. Specimens are tested in the dry (as received) condition. The Rated Siding specimens shall also be tested following the wetting cycle defined in ASTM E-72. Test Procedure Deflection measurements are recorded as the wall is being loaded. At least 10 sets of uniformly spaced deflection readings are taken prior to failure to establish the load-deformation curve. At 1-times and 2-times the test load specified in the appropriate Standard, the load is removed and the wall is allowed to recover for 5 minutes. At 2.5-times the test load, the dial gages are removed and the wall is loaded to failure. Deflections are reported with panel uplift, base slip and crushing removed. Ultimate load is recorded. APA METHOD S-4 FASTENER-HOLDING PERFORMANCE May 20, 1986 General Tests are made to measure the single-shear resistance of a nail to lateral movement of the panel. The procedure develops data which may be compared to other panel products, but does not produce joint design information. Direct withdrawal and nail head pull-through loads are also measured. Specimen Preparation Lateral Loads. Each specimen shall measure 6 x 6 inches. To serve as test points, four points shall be marked on the centerline of each specimen axis, 1 inch in from each edge. Nail size shall be as required. Sheathing material shall be stored in a room having a controlled temperature of 68 ± 6 F and a controlled relative humidity at 65 ± 3% to bring it to constant weight. Constant weight is assumed when two consecutive readings taken at least 24 hours apart agree within 0.2 percent. Nails shall be driven perpendicular to the face of the panel following conditioning. Nail penetration shall be such that the nail head lies flush with the panel face. A backing is used to prevent the nail from tearing away the back during driving. All nails shall be driven immediately prior to testing. Direct Withdrawal Loads. Test specimens shall be of convenient size (at least 3 inches by 6 inches) trimmed from the lateral resistance specimens. Nail size shall be as required. Nails shall be driven through the panel at right angles to the face and at least 1/2 inch of the shank portion shall project above the surface of the material. 40

43 FIGURE 1. Exploded View of APA Test Apparatus for Measuring the Lateral Nail-Holding Capacity of Structural Panel Products Loading head Metal foundation Metal grips Test specimen Lateral rollers 41

44 Nail Head Pull-Through Loads. Test specimens shall be of convenient size (at least 3 inches by 6 inches). Nail size and type shall be as required. Nails shall be driven through the panel at right angles to the face. Nail penetration shall be such that the nail head lies flush with the panel face. A backing is used to prevent the nail from tearing away the back during driving. All nails shall be driven immediately prior to testing. Rated Siding specimens shall be tested in the dry (as-received) condition and following seven days of wetting on one side. Conditioning. Prior to testing, the specimen may be subjected to conditioning as specified in ASTM E-661. Test Procedure Lateral Loads. The fastener is to be loaded in single shear. Apparatus similar to that shown in Figure 1 shall be employed. The nail shank shall be rigidly clamped. Rollers are present to insure vertical movement by providing lateral restraint to the panel. Load shall be applied through a yoke-type loading head. This loading head is also described in Figure 1. Direct Withdrawal Loads. Nail holding tests shall be made on nails driven through the thickness of the panel to measure the resistance to withdrawal in a plane normal to the face. Method of loading shall be in accordance with the most recent edition of ASTM D-1761, Section The specimen shall be loaded continuously throughout the test by uniform motion of the movable head of the testing machine at a rate of 0.2 inch per minute. Nail Head Pull-Through Loads. Nail head pullthrough tests shall be made on nails driven through the thickness of the panel to measure resistance to nail head embedment in a plane normal to the face. Method of loading shall be in accordance with the most recent edition of ASTM D-1037 Sections The specimen shall be loaded continuously throughout the test by uniform motion of the movable head of the testing machine at a rate of 0.20 inch per minute. The test specimen shall be loaded continuously throughout the test by uniform motion of the movable crosshead of the test machine at a rate of 0.20 inch per minute. March 11, 1980 APA METHOD S-5 PANEL BENDING General This test procedure provides basic data regarding full panel bending strength and stiffness. The general provisions of ASTM D-3043 Method C are followed. Specimen Preparation Test Procedure The procedures of ASTM D-3043 Method C are followed except specimens are tested for stiffness both along and across the major panel axis, and maximum bending moment is taken as required. Specimens are prepared according to ASTM D-3043 Method C, except specimen size shall be 4 x 4-foot half panels. 42

45 APA METHOD S-6 SMALL SPECIMEN BENDING FOR QUALITY ASSURANCE April 15, 1981 General Test method is intended to develop strength information which acts as a measure of bond integrity. Generally the test is run on moisture cycled specimens. Specimen Preparation Five 1-inch by 5-inch test specimens are to be cut from each sample to be tested. If testing is for Qualification, 15 specimens shall be cut from each sample to be tested (15 from each direction in the case of panels which exhibit directional properties). Side-by-side matching shall be observed for comparison of Control, D-4 and D-5 exposures. Specimens prepared from veneer-containing panels shall be cut with the grain of the veneer parallel to the 5-inch dimension. Specimens prepared from nonveneer panels shall be cut so that the 5-inch dimension of the specimens is parallel to the major panel axis except in the case of panels exhibiting directional properties, in which case five specimens shall be cut parallel and five perpendicular to the major panel axis. Specimens are then tested following appropriate treatment. Test Procedure Each specimen is tested as a beam across a 4-inch clear span with the loading head and supports measuring 3/4 inch in diameter. The load is applied at midspan at a rate not to exceed one inch per minute until failure occurs. Specimens from veneered composite panels will be oriented so that the thickness of the specimen acts as the depth of the beam. Specimens from nonveneer panels will be oriented so that the one-inch cut dimension acts as the depth of the beam and the panel thickness acts as the beam width. The breaking load for each specimen shall be measured to ± 1 pound. The average breaking load for each panel shall be calculated. In the case of other panels which exhibit directional properties, separate averages shall be determined for each specimen direction. Average values shall be reported. APA METHOD S-7 INTERNAL BOND March 11, 1980 General This method measures internal bond by ASTM D- 1037, Sections 28 to 33, Tensile Strength Perpendicular to Surface. Test Procedure The procedures of ASTM D-1037 Sections 28 to 33 are followed. Specimen Preparation From each sample five specimens are cut. The specimens are tested in the as-received condition. 43

46 APA METHOD S-8 TORQUE March 11, 1980 General This method measures internal bond by the torque method described by Shen and Carroll. (a) Equipment A dial torque wrench calibrated in inch-pounds of torque with a maximum reading indicator and a range of 300 inch-pounds is required. A pair of one-inch 8- point sockets is also required with the lower socket modified to include an adjustable platform to control specimen height and a plunger to eject the specimen after breaking. Specimen Preparation Test Procedure The lower socket is secured in a vise and the platform adjusted so that the centerline of a 1-inch square specimen is at the interface between the upper and lower sockets. A torsion force is applied to the specimen until failure occurs. The torsion load is read from the maximum load needle on the dial. Average torque values per panel and the overall average are reported. (a) K.C. Shen and M. N. Carroll A new method for evaluation of internal bond strength of particleboard. Forest Products Journal Vol. 19 number 8. From each sample five 1-inch by 1-inch squares are cut. The specimens are tested in the as-received condition. May 20, 1986 APA METHOD S-9 SIDING PERFORMANCE UNDER CONCENTRATED STATIC LOADS General This method covers a procedure for determining the performance of siding products under concentrated static loads, such as a ladder resting against a vertical wall. Residual indentation and deflection, and puncture resistance are measured. Siding panels are subjected to concentrated loads applied through a 1-inch (25-mm)-diameter loading rod. Equipment Supports. The framing members shall be supported in order not to deflect under the applied loads. The support conditions shall include all wall framing elements including top and bottom plate. Loading Device. Any convenient means may be used for applying a compressive load up to ultimate, and for measuring the load within plus or minus 1% accuracy. 44

47 Loading Rod. A loading rod one inch in diameter is required. The edge of the loading rod contacting the test specimen shall be rounded to a radius not to exceed 0.06 inch. Deflection Gages. A deflection gage shall be mounted rigidly to the loading rod. The deflection gage should have a range exceeding the maximum anticipated deflection, have a maximum error of plus or minus 1%, and be graduated to inch. To measure indentation, a metal sleeve shall be fabricated to fit around the loading rod. The bottom of the sleeve shall be chamfered to create a 1/4-inch-wide bearing ring around the rod. Clearance between the rod and the sleeve shall be approximately inch to prevent the sleeve from tilting, yet allow it to slide freely. The dial gage shall be mounted on the rod with its tip contacting the top of the sleeve. A second dial gage shall be mounted rigidly beneath the loading rod with its tip contacting the back side of the siding product. Specimen Preparation Samples shall be selected that are representative of the product being evaluated. A specimen can usually be made from a single panel, or assembled from a number of boards. Length. Specimen length parallel to the main framing members shall conform to the intended application. Width. Specimen width perpendicular to the main framing members shall conform to the center-to-center spacing, S, anticipated in service. Specimen width shall be equal to the minimum number of spans permitted or recommended for the product used in its intended application, multiplied by the center-to-center spacing of the framing members. Conditioning. Prior to static testing, siding shall be subjected to wetting or drying to simulate possible typical in-service conditions. Siding products may be tested under dry or wet conditions. Dry tests. Siding shall be conditioned to either constant weight or moisture content, or for at least two weeks at 68 plus or minus 6 F (20 plus or minus 3 C) and 65 plus or minus 5% relative humidity. Wet tests. Siding shall be exposed to a continuous water spray for seven days applied to the top surface of the siding at a rate such that this surface is kept continually wet. The siding shall be positioned so as to preclude water ponding on it or immersion of any portion. Test Procedure The concentrated load shall be applied to an outside span. The concentrated load shall be applied at midlength of the specimen. If the siding product is a lap product, the concentrated load shall be applied at midwidth of a single lap located at mid-length of the specimen. The concentrated load shall be applied midway between the framing members if the siding product is not grooved. If the siding product is grooved, the concentrated load shall be applied to a groove nearest to the midpoint between framing members. Residual indentation shall be measured relative to the siding product surface using a one-inch-diameter loading rod. Residual deflection shall be measured relative to the framing members. Indentation and deflection shall be recorded at 0 lb. The load shall be applied continuously at a rate of 0.04 inch/minute. The siding product shall be loaded to a 100-lb increment, the load removed, and the specimen allowed to recover for one minute. Indentation and deflection shall again be recorded at 0 lb. Residual values at the test location are the difference between the original gage reading at 0 lb and the second gage reading, taken after the 100-lb proof load. Following measurement of residual indentation and deflection, the load shall be reapplied at a rate of 0.2 inch/minute, until maximum load occurs. 45

48 APA METHOD S-10 SIDING PERFORMANCE UNDER UNIFORM LOADS May 20, 1986 General This method covers a procedure for determining the performance of siding products under uniform loads, such as a wind load, against a vertical wall. Strength and residual deflection are measured. Siding panels are subjected to uniform loads through use of atmospheric pressure in a vacuum test frame. Equipment Supports. The framing members shall be supported in order not to deflect under the applied loads. The support conditions shall include all wall framing elements including top and bottom plates. Vacuum Chamber. An external frame shall be fabricated large enough to enclose the test specimen. The chamber must be strong and rigid to resist the applied load without failure or excessive deformation. The floor and walls of the test chamber must be sealed sufficiently to prevent airflow in and out of the chamber. Following placement of the test specimen within the chamber, a 6-mil polyethylene sheet is laid over the specimen and taped to the frame to obtain an airtight seal. Air is removed from the chamber through use of a vacuum pump. The load is measure with absolute pressure gages for electronic data readout, but manometers or vacuum gages may also be used. Deflection Gage. The deflection gage shall be mounted on a rigid tripod. The legs of the tripod shall rest on the siding immediately above the framing, adjacent to the span being loaded. The deflection gage should have a range exceeding the maximum anticipated deflection, have a maximum error of plus or minus 1%, and be graduated to inch. Specimen Preparation Samples shall be selected that are representative of the product being evaluated. A specimen can usually be made from a single panel, or assembled from a number of boards. Length. Specimen length parallel to the main framing members shall conform to the intended application. Width. Specimen width perpendicular to the main framing members shall conform to the center-to-center spacing, S, anticipated in service. Specimen width shall be equal to the minimum number of spans permitted or recommended for the product used in its intended application, multiplied by the center-to-center spacing of the framing members. Conditioning. Prior to testing, siding shall be subjected to wetting or drying to simulate possible typical in-service conditions. Siding products may be tested under dry or wet conditions. Dry tests. Siding shall be conditioned to either constant weight or moisture content, or for at least two weeks at 68 plus or minus 6 F (20 plus or minus 3 C ) and 65 plus or minus 5% relative humidity. Wet tests. Siding shall be exposed to a continuous water spray for seven days applied to the top surface of the siding at a rate such that this surface is kept continually wet. The siding shall be positioned so as to preclude water ponding on it or immersion of any portion. Test Procedure The deflection shall be measured on each outside span. The deflection shall be measured at mid-length of the specimen. If the siding product is a lap product, the deflection shall be measured at mid-width of a single lap located at mid-length of the specimen. The deflection shall be measured at the theoretical point of maximum deflection. The point of maximum deflection for a uniformly loaded two-span system occurs at (S) measured from the centerline of the outer support, where S equals the center-to-center support spacing. The point of maximum deflection for a uniformly loaded three-span system occurs at (S) measured from the centerline of the outer support, where S equals the center-to-center support spacing. Residual deflection shall be measured relative to the framing. 46

49 Deflection shall be measured at 0 psf. The load shall be applied continuously at a rate of 25 psf/minute. The siding product shall be loaded to 50 psf, the load removed and the section allowed to recover for one minute. Panel deflection shall again be recorded at 0 psf. Residual deflection at the test location is the difference between the original deflection gage reading at 0 psf and the second deflection gage reading, taken after the 50 psf proof load. Following measurement of residual deflection, the load shall be reapplied at a rate of 25 psf/minute, until maximum load occurs. APA METHOD S-11 SIDING PERFORMANCE UNDER HARD-BODY IMPACT LOADS May 20, 1986 General This method covers a procedure for determining the performance of siding products under hard-body impact loads, such as foot kicks, hailstones, or hammer blows to a vertical wall. Residual indentation and puncture resistance are measured. Siding panels are subjected to hard-body impact loads applied through a 2-lb steel ball, 2-3/8 inches in diameter. Equipment Supports. The framing members shall be supported in order not to deflect under the applied loads. The support conditions shall include all wall framing elements including top and bottom plates. Impact Ball. The steel ball shall be 2-3/8 inches in diameter, and shall weigh 2 lb. Loading Device. An apparatus shall be designed suitable for holding and releasing the impact ball from predetermined heights. Measuring Rod. A measuring rod graduated in 6-inch increments and equipped with a sliding pointer shall be used to measure the drop height of the impact ball. Deflection Gage. A deflection gage shall be mounted rigidly to a tripod. The legs of the tripod shall rest on the siding immediately above the framing members. The deflection gage should have a range exceeding the maximum anticipated deflection, have a maximum error of plus or minus 1%, and be graduated to inch. Specimen Preparation Samples shall be selected that are representative of the product being evaluated. A specimen can usually be made from a single panel, or assembled from a number of boards. Length. Specimen length parallel to the main framing members shall conform to the intended application. Width. Specimen width perpendicular to the main framing members shall conform to the center-to-center spacing, S, anticipated in service. Specimen width shall be equal to the minimum number of spans permitted or recommended for the product used in its intended application, multiplied by the center-to-center spacing of the framing members. Conditioning. Prior to hard-body impact testing, siding shall be subjected to wetting or drying to simulate possible typical in-service conditions. Siding products may be tested under dry or wet conditions. Dry tests. Siding shall be conditioned to either constant weight or moisture content, or for at least two weeks at 68 plus or minus 6 F (20 plus or minus 3 C) and 65 plus or minus 5% relative humidity. Wet tests. Siding shall be exposed to a continuous water spray for seven days applied to the top surface of the siding at a rate such that this surface is kept continually wet. The siding shall be positioned so as to preclude water ponding on it or immersion of any portion. 47

50 Test Procedure The hard-body impact load shall be applied to an outside span. The hard-body impact load shall be applied 4 inches either side of mid-length of the specimen. If the siding product is a lap product, the hard-body impact load shall be applied at mid-width of a single lap located at 4 inches either side of mid-length of the specimen. The hard-body impact load shall not be applied to a span which has been previously tested for soft-body impact resistance. The hard-body impact load shall be applied midway between the framing members if the siding product is not grooved. If the siding product is grooved, the hard-body impact load shall be applied to a groove nearest to the midpoint between framing members. Prior to impact a gage reading shall be recorded at the load point. The impact ball shall be dropped at the test location on the top surface of the siding product in 6-inch increments during the test. Residual indentation shall be measured relative to the framing under the load point. One minute following the 24-inch drop, a deflection gage reading shall be measured at the load point. Residual indentation at the test location is the difference between the initial deflection gage reading and the second deflection gage reading taken after the 24-inch drop. Following measurement of residual indentation, the hard-body impact test shall be continued at 6-inch drop increments. The test shall stop when a visible fracture occurs at the bottom of the specimen. The height of the drop that produces the first visible fracture shall be recorded. APA METHOD S-12 SIDING PERFORMANCE UNDER SOFT-BODY IMPACT LOADS May 20, 1986 General This method covers a procedure for determining the performance of siding products under soft-body impact loads, such as a person running or falling against a vertical wall. Residual indentation and loadcarrying capacity are measured. Siding panels are subjected to soft-body impact loads applied through a 30-lb leather shot bag. Equipment Supports. The framing members shall be supported in order not to deflect under the applied loads. The support conditions shall include all wall framing elements including top and bottom plates. Drop Bag. The drop bag shall be constructed in accordance with ASTM E Standard Test Method for Performance of Wood and Wood-Based Floor and Roof Sheathing Under Concentrated Static and Impact Loads, Sections Measuring Rod. A measuring rod graduated in 6-inch increments and equipped with a sliding pointer shall be used to measure the drop height of the bag. Deflection Gage. A deflection gage shall be mounted rigidly to a tripod. The legs of the tripod shall rest on the siding immediately above the framing members. The deflection gage should have a range exceeding the maximum anticipated deflection, have a maximum error of plus or minus 1%, and be graduated to inch. Specimen Preparation Samples shall be selected that are representative of the product being evaluated. A specimen can usually be made from a single panel, or assembled from a number of boards. Length. Specimen length parallel to the main framing members shall conform to the intended application. 48

51 Width. Specimen width perpendicular to the main framing members shall conform to the center-to-center spacing, S, anticipated in service. Specimen width shall be equal to the minimum number of spans permitted or recommended for the product used in its intended application, multiplied by the center-to-center spacing of the framing members. Conditioning. Prior to soft-body impact testing, siding shall be subjected to wetting or drying to simulate possible typical in-service conditions. Siding products may be tested under dry or wet conditions. Dry tests. Siding shall be conditioned to either constant weight or moisture content, or for at least two weeks at 68 plus or minus 6 F (20 plus or minus 3 C) and 65 plus or minus 5% relative humidity. Wet tests. Siding shall be exposed to a continuous water spray for seven days applied to the top surface of the siding at a rate such that this surface is kept continually wet. The siding shall be positioned so as to preclude water ponding on it or immersion of any portion. Test Procedure The soft-body impact load shall be applied to an outside span. The soft-body impact load shall be applied at mid-length of the specimen. If the siding product is a lap product, the soft-body impact load shall be applied at mid-width of a single lap located at midlength of the specimen. The soft-body impact load shall be applied midway between the framing members. Prior to impact, a deflection gage reading shall be recorded at the load point. The bag shall be dropped at the test location on the top surface of the siding product in 6-inch increments during the test. Residual deflection shall be measured relative to framing under the load point. One minute following the 12-inch drop, deflection shall be measured at the load point. Residual deflection at the test location is the difference between the initial deflection gage reading and the second deflection gage reading taken after the 12-inch drop. Following measurement of residual deflection, the softbody impact test shall be continued at 6-inch drop increments until the bag falls through the siding product. The drop height at which this occurs shall be recorded. APA METHOD S-13 PANEL COMPRESSION May 20, 1986 General This test procedure provides basic data regarding compression properties of panel products. The general procedures of ASTM D-3501 Method B are followed. Test Procedure The procedures of ASTM D-3501 Sections are followed. Specimen Preparation From each sample, one specimen is cut. The specimens are tested in the as-received condition unless otherwise specified. 49

52 APA METHOD S-14 SMALL SPECIMEN STATIC BENDING May 20, 1986 General This test method measures small specimen static bending strength and stiffness. The test method is fully described in ASTM D-1037, Sections 11-20, Static Bending, except specimen width shall be 4-1/2 inches. Specimen Preparation The specimens are tested in the as-received condition. Test Procedure The procedures of ASTM D-1037 Sections are followed. 50

53 APA METHOD P-1 LINEAR EXPANSION AND THICKNESS SWELL MEASURED FROM OVEN DRY TO VACUUM-PRESSURE-SOAK May 20, 1986 General This test method provides a quick evaluation of a panel s dimensional stability. Specimen Preparation Test specimens are cut at least 3 inches wide by at least 12 inches long. Specimens should be selected to avoid large characteristics such as knotholes, knots, or splits in the outer veneers (when veneers are present), especially near the eyelet locations. Otherwise, normal grade features are included as they occur. Brass eyelets placed in pre-bored holes or other fixed reference points which serve as measuring points on the centerline of each specimen are located 1 inch in from each end. Use of the reference measuring points permits determination of linear expansion independent of any additional swelling that might take place at the exposed panel edge. Additionally, points shall be marked on the edges of each specimen for thickness swell evaluation. Thickness is measured according to Test Method P-7, except as modified below. Test Procedure Specimens are oven dried at 217 ± 4 F for 24 hours or until constant weight is attained. Constant weight is assumed when two consecutive readings taken at least two hours apart agree within 0.2 percent. After drying, each specimen is wrapped in polyethylene and allowed to cool to approximately room temperature. The specimen is then placed in a flattening jig to remove any out-of-plane distortions, and the distance between gage points measured to the nearest inch with a bar-type trammel equipped with a dial gage. At least two thickness measurements are made with a rachet type micrometer to the nearest inch with the anvil edge flush with the specimen edge. The micrometer shall be as described in APA Test Method P-7. Following the dry measurements, specimens are placed in a pressure cylinder, flooded with 65 ± 10 F tap water and subjected to a vacuum of 27 ± 2 inches of mercury for one hour (time does not begin until full vacuum is achieved). Specimens are then subjected to two hours of pressure not to exceed 100 pounds per square inch. (a) After wet exposure, specimens are removed from the cylinder and remeasured for length and thickness. Expansion values are calculated as a percentage of the original oven-dry dimension, as given in the equation below: Percent change = L w L d x 100 L d where L w = dimension saturated where L d = dimension oven dry (a) For product evaluation and quality assurance testing, atmospheric pressure is used for the pressure-soak cycle of the test. 51

54 APA METHOD P-2 LINEAR EXPANSION AND THICKNESS SWELL MEASURED AFTER WETTING ON ONE SIDE May 20, 1986 General This performance test is designed to measure linear expansion and edge thickness swell as it may occur in service. Specimen Preparation Each 4-foot by 4-foot specimen shall have only one cut edge, the remaining three being as prepared by the manufacturer. To serve as measuring points for linear expansion, brass eyelets are placed in four prebored holes on the centerline of each specimen axis, one inch in from each edge. This results in a nominal 46-inch gage distance both along and across the major panel axis. Additionally, points shall be marked on each uncut side of the specimen for thickness swell evaluation. Thickness is measured according to Test Method P-7. Moisture content (oven-dry basis) is measured according to APA Test Method P-6 prior to testing in a panel from the same lot. Should the moisture content of the specimens exceed 12%, they shall be conditioned to constant weight at 68 ± 6 F and 65 ± 5% relative humidity to achieve an equilibrium moisture content. Constant weight is assumed when two consecutive readings taken at least 24 hours apart agree within 0.2 percent. Test Procedure Linear expansion specimens are placed in a flattening jig to remove any out-of-plane distortions, and the distance between gage points measured to the nearest inch with a bar-type trammel equipped with a dial gage. Thickness is measured along the edge to the nearest inch with a dial gage micrometer, applying ratchet pressure during measuring. Following these as-received measurements, unrestrained specimens are mounted within 30 degrees of vertical and are wetted on one side with water at 65 ± 10 F. The period of continuous wetting shall be 14 days for Rated Sheathing and Rated Sturd-I-Floor and 21 days for Rated Siding. No liquid water shall impinge on the back. The back shall be exposed to any humidity vapor present. All factory edges shall be exposed to water except the freshly cut edge. The cut edge should be the top edge and may be protected with an edge sealer. After wet exposure the specimens are remeasured. Expansion values are calculated to express results as a percentage of the original dimension, as given in the equation: Percent change = L w L d x 100 L d where L w = dimension wet where L d = dimension dry 52

55 APA METHOD P-3 LINEAR AND THICKNESS EXPANSION MEASURED BY EXPOSURE TO RELATIVE HUMIDITY August 12, 1980 General This method measures linear expansion in accordance with ASTM D-1037, Sections 107 to 110, Linear Variation with Change in Moisture Content. Thickness expansion, where applicable, is measured as described below. The exposure to relative humidity change from 50 to 90% is an indication of extreme service conditions. Specimen Preparation From each sample, two specimens are cut according to the procedures of ASTM D-1037, Sections 107 to 110. Test specimens are cut 3 inches wide by 41 inches long. Shorter lengths may be used, but specimens should not be less than 12 inches long. To serve as measuring points for linear expansion, brass eyelets are placed in pre-bored holes on the centerline of each specimen, 1 inch in from each end. This results in a nominal 39-inch gage distance. Additionally, points shall be selected and marked on the centerline of the specimen 3 inches in from each end to serve as measuring points for thickness expansion. Test Procedure The procedures of ASTM D-1037 Sections 107 to 110 are followed for linear expansion testing, except that specimens are placed in a flattening jig to remove any out-of-plane distortions, and the distance between gage points is measured to the nearest inch with a bartype trammel equipped with a dial gage. Thickness is measured to the nearest inch with a dial gage micrometer, applying ratchet pressure during measuring. Expansion values are calculated to express results as a percentage of the original dry dimension, as given in the equation: Percent change = L w L d x 100 L d where L w = dimension wet where L d = dimension dry 53

56 APA METHOD P-4 LINEAR EXPANSION MEASURED IN A FULL-SCALE FRAME March 11, 1980 General This full-scale test procedure is an estimate of panel performance in a structure when wet. Specimen Preparation Eight 4-foot by 8-foot panels are required. No preconditioning or other procedures are used on the panels; they are used as received. Two panels are cut into 4-foot by 4-foot pieces for the assembly. A 16-foot by 16-foot lumber frame is constructed using 2x8 No. 2 or better hem-fir lumber or equivalent. The lumber is end nailed through a band joist at the required support spacing with three 16d common or double-headed nails. Panels are installed with major panel axis across the framing and with end joints staggered four feet. End and edge spacing and nailing schedule is carefully maintained according to application recommendations prescribed in the specification. Test Procedure Overall dimensions of the assembly are measured on the panel surface at the ends and middle for both along and across the major panel axis. A continuous water spray is then applied to the top surface with a common garden sprinkler for 14 consecutive days. Following wetting, the panel measurements are again taken. Percent expansion for both directions is then calculated as follows: Percent change = L w L d x 100 L d where L w = length wet where L d = length dry The average for each direction is then calculated from the individual readings. 54

57 APA METHOD P-5 PANEL STABILITY INDEX FOR SHEATHING AND STURD-I-FLOOR August 12, 1980 General This method produces an indication of a panel s threshold point for buckling when wet. Specimen Preparation Following flexure testing of each 4-foot by 4-foot specimen (see Test Method S-5), specimens shall be cut in each panel direction according to APA Test Method P-1 for linear expansion from oven-dry to soak. Test Procedure As an indication of the ability of the product to remain flat in service when applied according to the manufacturer s recommendations, a stability index shall be calculated using the panel properties of stiffness and coefficient of linear expansion, as well as the intended span. Flexural stiffness of each 4-foot by 4-foot specimen shall be determined in each panel direction by the procedures given in APA Test Method S-5. Linear expansion shall be measured from oven dry to soak. The procedures given in APA Test Method P-1 shall be followed. The stability index for each direction of each specimen is then calculated as: A = log 10 [π 2 EI / L 2 φ] where A = stability index EI = stiffness (lb-in. 2 /ft) φ = linear expansion (in./in.) (Percent expansion divided by 100) L = span (in.) For the major panel axis, the span shall be the maximum span rating for which the panel is being qualified. For the cross-panel direction, the span is the maximum recommended interior nail spacing (generally 10 or 12 inches). 55

58 APA METHOD P-6 PANEL MOISTURE CONTENT March 11, 1980 General This test procedure defines the method of determining panel moisture content by the oven-dry method according to the principles of ASTM D-4442, Method B. Specimen Preparation From each panel cut a specimen at least two inches from any edge using a three-inch hole saw. If the panel size is less than 6 inches by 6 inches (by panel thickness) the entire panel should be used. Test Procedure The specimen weight is obtained (± 0.2%) and placed in a drying oven at 217 ± 4 F until constant weight is achieved. Constant weight is assumed when two consecutive readings taken at least two hours apart agree within 0.2 percent. The moisture content is calculated as: M = [(W w W d )/W d ] 100 where M = Moisture content (percent) W w = Initial weight (grams or similar units) W d = Oven-dry weight (grams or similar units) APA METHOD P-7 PANEL THICKNESS March 11, 1980 General This method defines the procedure for determining panel thickness. Specimen Preparation The readings are taken on an as-received panel. Test Method For each panel, one thickness reading is taken midwidth on each panel edge such that the anvil does not touch the extreme edge. Measurements will be taken to the nearest ± inch using a micrometer with 0.75 ( 0, )-inch-diameter anvils. The micrometer will apply a pressure of not less than 5 psi or more than 10 psi during measurement. The panel thickness shall be the average of four readings. 56

59 APA METHOD P-8 PANEL DENSITY (a) March 11, 1980 General This procedure measures panel density in pounds per cubic foot. Specimen Preparation Each sample is carefully cut to 12 inches by 12 inches (or other suitable size). The specimen shall be cut such that the diagonals do not vary more than 0.2 percent from each other. Samples are measured based on oven-dry weight and the as-received volume. Test Procedure Each specimen is measured for thickness at the four corners, in from the edge 1/2 inch using the micrometer described in APA Test Method P-7. The panel dimensions are measured to the nearest ± 0.05 inch. The specimen is then weighed to the nearest ± 0.10 gram. A three-inch-wide moisture content sample is then cut from the edge and moisture content determined according to APA Test Method P-6. Panel density is then calculated as: D = W/ (L1 x L2 x T) where L1 = Average length of side one (inches) L2 = Average length of side two (inches) T = Average panel thickness (inches) W = Weight (grams) Panel density is reported with the associated moisture content. (a) Panel density may be determined in accordance with ASTM D-1037, Section 124 to 125, Moisture Content and Specific Gravity, as an alternate method at mill option. 57

60 APA METHOD P-9 PROBE FOR DELAMINATION April 15, 1981 General This test method defines a method for the determination of delamination in composite panels. Equipment The probe used shall measure 1/4 inch wide at the tip by inch thick and shall taper in thickness to about inch one-half inch from the tip. The 1/4 inch width shall taper to a width of 5/8 inch at 1 inch from the end. The probe can be any convenient length. The end of the probe is to be squared off and not sharp so that when probing delaminations, fibers across the delaminated area will not be cut. Specimen Preparation Test Procedure Delamination shall be evaluated according to the following procedure. The specimen is examined visually for delamination. Any separations in the specimen periphery in veneer-to-veneer or veneer-to-woodbased material glueline are probed to determine depth of delamination. A separation that is 1/4 inch deep for one continuous inch is considered as having failed the test for delamination. Use of slight pressure will be necessary when inserting the probe into the delaminated areas. The pressure is to be limited to that which can be applied by gripping the probe between the thumb and first finger. In no case is any prying action to be used. Number of specimens failing this test is reported. Five specimens shall be cut from each sample to 1-inch by 5-inch dimensions, avoiding veneer defects when present, with grain of the outer plies in the long direction. Measurement will take place prior to any mechanical test. 58

61 APA METHOD P-10 PANEL STABILITY COEFFICIENT FOR SIDING May 20, 1986 General This method produces an indication of a siding panel s threshold point for buckling when exposed to onesided wetting. Specimen Preparation Each 4-foot by 4-foot siding specimen is tested for linear expansion after three weeks of one-sided wetting (see Test Method P-2). Siding specimens are immediately tested for bending stiffness in each direction (see Test Method S-5) with the siding face in tension. Specimens are then cut for compression testing according to Test Method S-13. Test Procedure As an indication of the ability of the siding product to remain flat in service when applied according to the manufacturer s recommendations, a stability coefficient shall be calculated using the panel properties of linear expansion and compressive stiffness after wetting exposure, as well as the intended span between supports. Linear expansion shall be measured after three weeks of one-sided wetting according to the procedures in APA Test Method P-2. Bending stiffness shall be measured after three weeks of one-sided wetting according to the procedures in APA Test Method S-5. Compressive stiffness shall be measured after three weeks of one-sided wetting according to the procedures in APA Test Method S-13. The stability coefficient for each panel direction is then calculated as: B=π 2 EI/(L 2 φ EA) where B = stability coefficient EI = bending stiffness (lb-in. 2 /ft) φ = linear expansion (inch/inch) EA = compressive stiffness (lb/ft) L = span (inch) For the cross-panel direction, the span shall be the Span Rating for which the panel is qualified. For the long panel axis, the span is the maximum recommended interior nail spacing (generally 12 inches). 59

62 APA METHOD P-11 BUCKLING PERFORMANCE MEASURED ON A LARGE-SCALE WALL May 20, 1986 General This large-scale wall procedure evaluates buckling performance of siding when exposed to one-sided wetting. Specimen Preparation A lumber frame measuring at least 8 feet by 12 feet is constructed using 2x4 stud grade or better hem-fir lumber. The frame construction simulates the intended end use of the panel, so the support spacing and other construction details will vary. The frame is clad with a sufficient amount of siding to completely cover the wall. Siding is applied in the asreceived condition. Panel direction relative to supports, end and edge spacing, nail spacing and all other fabrication details are carefully maintained according to the application recommendations for the particular end use of the panels. Test Procedure Overall dimensions of the assembly are measured on the siding surface to the nearest 0.01 inch at the ends and middle for both along and across the major panel axis. A continuous water spray is then applied to the top surface for 21 consecutive days. Following wetting, the panel measurements are again taken. Percent expansion for both directions is then calculated as follows: The average for each direction is then calculated from the individual readings. Buckling between supports is measured along at least three horizontal profiles. For siding panels applied parallel to supports on an 8-foot by 12-foot wall, the buckling between studs is measured along horizontal profiles at 2, 4 and 6 feet from the top of the wall. Buckling is also measured at any other horizontal location showing maximum distortion. Buckling along supports is measured along at least five supports. Buckling between supports is measured as the deviation from a straight line between adjacent supports. Buckling or other distortions along supports are measured as a deviation from a straight line between adjacent fasteners. Buckling measurements are made at equally spaced locations along each profile. At least 6 measurements are taken between each support along or between each fastener along each support. Separate data populations are formed from distortion measurements between supports and along supports. The upper five percent exclusion limit is determined on each population. Percent change = L w L d x 100 L d where L w = length wet where L d = length dry 60

63 APA METHOD P-12 PROBE FOR EDGE CHECKING OF SIDING May 20, 1986 General This method evaluates drip edge checking of siding panels after exposure to one-sided wetting. Equipment The probe shall measure 1/4-inch wide at the tip by inch thick and shall taper in thickness to about inch at one-half inch from the tip. The 1/4-inch tip width shall taper to a width of 5/8 inch at 1 inch from the end. The probe can be any convenient length. The end of the probe is to be squared off and not sharp so that when probing delaminations, fibers across the delaminated area will not be cut. Specimen Preparation Specimens shall be cut and exposed to three weeks of one-sided wetting according to the procedures of Test Method P-2. Specimens used for Test Method P-11 may be used as an alternate. Test Procedure Edge checking shall be evaluated along the bottom drip edge and along any groove walls according to the following procedure. The specimen is visually examined for any edge separations in the woodbased panel substrate excluding those which occur between adjacent veneers. A separation that allows the probe 1/8-inch penetration is considered as having failed the test for edge checking. Use of slight pressure will be necessary when inserting the probe into the separated areas. The pressure is to be limited to that which can be applied by gripping the probe between the thumb and the first finger. In no case is any prying action to be used. Number of specimens failing this test is reported. The above procedure is repeated after the specimens are redried to conditions at 65% relative humidity and 68 degrees Fahrenheit. Equilibrium to these conditions is established when the test specimen s weight changes less than 0.2 percent between two consecutive readings taken at least 24 hours apart. 61

64 APA METHOD F-1 SURFACE CHANGE MEASURED AFTER SOAK-DRY CYCLES May 20, 1986 General This method describes the procedure for determining change in surface profile of wood-based sidings after they have been subjected to five soak-dry cycles. Equipment Equipment that is capable of moving a stylus over a test surface at a constant speed of 1 inch per minute and transferring the traced profile to graph paper. Chamber capable of conditioning test specimens under conditions of 50 ± 5% relative humidity and 68 ± 5 F. Container large enough to submerge test specimens in water at 75 ± 5 F and oven with forced air circulation to dry specimens at 145 ± 5 F. Specimen Preparation Specimens approximately 10 x 12 inches, with the long dimension perpendicular to the surface pattern shall be cut from each product sample. For non-patterned surfaces, the long dimension is parallel to the major axis. For panel products, cut one specimen from the center of one quadrant; one specimen from the center of the diagonally opposite quadrant and a third specimen from the center of the panel. For lap siding, cut three specimens, randomly selected along the siding. Apply one light coat of white all-acrylic latex paint to the surface to be evaluated. Draw a straight pencil line down the middle of each specimen parallel to the long dimension. Test Procedure Condition specimens to equilibrium moisture content at approximately 50 ± 5% relative humidity and 68 ± 5 F. Equilibrium is assumed when two consecutive readings taken at least 24 hours apart agree within 0.2%. Record surface roughness along an 8 length of the pencil line by moving the stylus over the test specimen at a constant speed of 1 inch per minute and recording a trace of the stylus movement on graph paper. Submerge specimen in water at 75 ± 5 F for eight hours and then dry to a constant weight at 145 ± 5 F in an oven which has forced air circulation. Constant weight is assumed when two consecutive readings taken at least two hours apart agree within 0.2%. This is one cycle. Repeat the soak-dry cycle a total of five times. Retrace the original profile and transfer profile to graph paper. 62

65 Calculations Weighted Roughness Evaluation of the profile trace involves calculating the Peak Index (PI) from a Weighted Roughness (WR) factor (refer to Figures 1 and 2). The WR is the sum of the products of the number of peaks or valleys multiplied by a weighting factor. The weighting factor for peak (valley) height gives more emphasis to the larger peaks (valleys) than the smaller ones. The roughness of the surface is expressed in a quantitative manner by using the surface profile to develop a Weighted Roughness (WR) factor and a Peak Index (PI). The method is summarized by an example in Figure 2. First a line is drawn through the center of the profile trace. This line is located so that it is midway between the highest peaks and lowest valleys on the trace. Equal zones are located above and below the center line. Each zone should represent ± inch actual relief on the panel s surface and be magnified at least 100 times in order to compute PI. Those zones located immediately above and below the center line are assigned a weighting factor of 1, and zones located farther away from the center line are assigned progressively higher numbers, as shown in Figure 2. While the number of zones shown in Figure 2 is four, above and below the center line, the number can vary depending on the roughness of the surface. The equation for weighted roughness is: WR = W f x N p [1] WR = Weighted roughness for that zone W f = Weight factor for the zone N p = Number of peaks within the zone Peak Index The Peak Index (PI) for each specimen is calculated by: PI = S wr S np Where: Surface Change [2] PI = Peak Index S wr = Sum of each zone WR S np = Sum of number of peaks Surface change (SC) is calculated as the difference between the Peak Index before soak-dry cycles and the Peak Index after moisture cycling. The equation is: SC = PI (cycled) PI (dry) [3] Where: SC = Surface change (absolute value) 63

66 Peaks C L Valleys FIGURE 1 Typical Profile Trace Total Weighted Roughness (WR) Count Weight Factor ΣWR Peak Index (PI) = Total No. of Peaks = 2.03 Peaks C L Valleys FIGURE 2 Calculation of Peak Index (PI) from Profile Trace 64

67 APA METHOD F-2 FINISH ADHESION ON WOOD-BASED SIDING May 20, 1986 General This method describes the procedure for determining the average initial adhesion of the standard control finish to sidings. The adhesion of a standard control solid-color stain to a wood-based siding product is determined by measuring the force required to remove, in a 180 peel, a 1-inch-wide strip of cotton cheesecloth which has been embedded in the stain. Equipment Apparatus that is capable of firmly holding test specimens, peeling the cotton cheesecloth from the specimens at a constant machine speed of 1 inch per minute and transferring the peel loads to graph paper or other media from which an average load value can be developed. A test chamber capable of curing finish on test specimens under conditions of 50 ± 5% relative humidity and 68 ± 5 F. Freshly prepared standard control finish. Formulation of finish given in Table 1. Specimen Preparation Specimens approximately 2 x 10 inches with the long dimension perpendicular to the direction of the surface pattern shall be cut from each product sample. For non-patterned surfaces, the long dimension is parallel to the major panel axis. For each test specimen, cut a sample of cotton cheesecloth (not woven synthetic cheesecloth) approximately 1-3/4 by 10 inches long made up of four single layers. Apply freshly prepared (one year or less and no visible changes in properties) standard control solid color stain (K-64-3, barn red, Rohm & Haas Co.) to one-half of siding specimen in a path approximately 2x5 inches. Lay one-half of the strip of cheesecloth (composed of four single layers) into this wet path and then thoroughly saturate it by brushing additional stain on top. Cure finish two weeks under conditions of approximately 50 ± 5% relative humidity and 68 ± 5 F. Test Procedure With a sharp knife or razor blade, down the length and along the center of the specimen (cut a 1-inch-wide strip in the cured finish). (Refer to Figure 1.) Hand separate the first 1/2 inch of finish-embedded cheesecloth from the substrate. Place the specimen in a testing machine which is capable of separating the cheesecloth from the substrate at a constant machine speed of 1 inch per minute (resulting in an actual separation rate of 1/2 inch per minute), and which can continuously record the peel load over the specified distance. (Refer to Figure 2.) Peel the cheesecloth for at least 2 inches and record the load curve. (Refer to Figure 3.) For adhesion to panel surface repairs, peel cheesecloth from repairs only while recording the load curve. Calculations From the load data determine the average peel load in pounds per inch of width. This may be an average determined visually from graph paper by drawing a line through the load curve so that equal portions of the curve are above and below the line. (Refer to Figure 3.) 65

68 TABLE 1. Formulation For Standard Control Finish, K-64-3 Parts Per Hundred Materials Weight Ratio* (Volume Basis) Tamol 731 (25%) Triton CF Foamaster VL Ethylene glycol Natrosol 250 MHR (2.5%) Water Red iron oxide, RO Red iron oxide, RO Silica Grind 5 minutes at high speed, then add: Attagel Grind 10 to 15 additional minutes and let down: Rhoplex AC-64 (60.5%) Foamaster VL Texanol Super Ad-It Natrosol 250 MHR (2.5% and/or water) Formulation Constants Pigment volume content 40.0% Volume solids 42.0% ph 9.2 Viscosity 82 to 86 KU ICI viscosity 1.0 to 1.2 poise * Using weight ratio in pound units will yield approximately 100 gallons of paint, while with kilograms, 833 liters will result. 66

69 FIGURE 1 Specimen Ready for Peel Test FIGURE 2 Testing Machine Adapted for Measurement of Peeling Load 67

70 lb per inch width Average Load FIGURE 3 Typical Peeling Load Curve APA METHOD F-3 SURFACE REPAIR PERFORMANCE IN WOOD-BASED SIDING May 20, 1986 General This method describes the procedure for determining the acceptability of surface repairs in siding. Equipment Container large enough for submerging specimens in boiling and room temperature water. Oven with forced air circulation. Metal probe (see equipment description in APA Test Method P-9). Equipment outlined in APA Test Method F-2. Specimen Preparation Test 1 Boil-Dry Specimens Cut 12 x 12-inch test specimens so that each contains a repair of maximum size intended for product. Test specimens shall have no edge sealing or protective coating. Test 2 Soak-Dry Specimens Cut 12 x 12-inch test specimens so that each contains a repair of maximum size intended for product. Test specimens shall have no edge sealing or protective coating. Test 3 Finishability Specimens Finish compatability. To each specimen apply one coat of K-64-3 standard acrylic solid-color control stain by brush. If finish shows signs of incompatability (e.g. alligatoring, crawling, etc.), the test repair is considered to be unsatisfactory for finishing and no further testing of finishability is required. If no signs of incompatibility are observed, prepare additional specimens as detailed in APA Test Method F-2. Test 4 Machinability Specimens Cut at least five test specimens containing repairs of maximum size intended for product from siding samples. 68

71 Test Procedure Test 1 Effect of Boil-Dry Cycles on Repair Durability Subject test specimens to 2 cycles of 4-hour immersion in boiling water followed by 20 hours of drying in an oven with forced air circulation at 145 ± 5 F. Power saw through repair. Examine the cohesive and adhesive bond of the repair and the repairsubstrate interface with the metal probe previously described. Test 2 Effect of Multiple Soak-Dry Cycles on Repair Durability Subject test specimens to 10 cycles of 4-hour immersion in water at 75 ± 5 F followed by 20 hours of drying in an oven with forced air circulation at 145 ± 5 F temperature. Power saw through the repair. Examine the cohesive and adhesive bond of the repair and the repair-substrate interface with the metal probe previously described. Test 3 Finishability of Surface Repairs Subject test specimens to finish adhesion testing, following procedure outlined under APA Test Method F-2. Test 4 Effect of Machinability on Surface Repairs Subject repairs to all machining tests or use additional specimens as necessary to provide specimens for each test. Follow good shop practice and use tools in good condition. Examine specimens for the ability of repairs to be machined satisfactorily and remain in place. 1. Sawing Cut through the filled defect with a table saw. Use carbide-tipped general purpose blade or suitable alternative in good condition. 2. Nailing Drive nails of the size recommended by the manufacturer through the panel and the filled area. Back the specimen solidly during nailing. 3. Drilling Power drill with a 1/4-inch-diameter machine bit through the filled area. Back the specimen solidly during drilling. 4. Routing Power rout a 1/2-inch-wide groove through the face and across the filled area. 69

72 APA METHOD F-4 OVERLAY PERFORMANCE ON WOOD-BASED SIDING May 20, 1986 General This method describes procedures for determining the acceptability of overlays on siding. An overlay must have an adequate bond to the substrate for the expected life of the siding, must resist the effects of weathering (not crumble, craze or crack), must accept and hold a finish, and must be machinable. Equipment Pressure vessel for saturating test specimens with water. Oven with forced air circulation. Metal probe (See equipment description in APA Test Method P-9). Specimen Preparation Test 1 Multiple Vacuum-Pressure-Dry Specimens Specimens 6 x 6 inches are cut from the siding samples. Test specimens shall have no edge seal or protective coating. Test 2 Machining Specimens Specimens approximately 12 x 12 inches or other size convenient for handling in the test are cut from the siding samples. Test Procedure Test 1 Effect of Multiple Vacuum-Pressure-Dry Cycles on Overlay Durability Subject specimens to three cycles of immersion in cold tap water in a pressure vessel under the following conditions. Draw approximately 25 inches of mercury vacuum and maintain it for 30 minutes. Then immediately apply psi of pressure for 30 minutes. Dry specimens for 20 hours at a temperature of 145 ± 5 F in an oven with forced circulation. This is one cycle. After each cycle: Visually inspect the overlay for delamination and cracks. Probe the edges of the overlay for delamination using a thin metal probe. Test 2 Effect of Machining on Overlay Performance Subject each overlay specimen to all machining tests or use additional specimens as required. Follow good shop practice and use tools in good condition. After each operation visually inspect the overlay for its ability to machine satisfactorily and mechanically probe the overlay for loss of cohesion or adhesion. 1. Sawing Cut through the overlay with a table saw. Use a carbide-tipped general purpose blade or suitable alternative in good condition. 2. Nailing Drive nails of the size recommended by the manufacturer through the overlay. Back the specimens solidly during nailing. 3. Drilling Power drill with a 1/4-inch-diameter machine bit through the overlay. Back the specimens solidly during the drilling. 4. Routing Power rout a 1/2-inch-wide groove through the overlay. 70

73 TRADEMARK EXAMPLES FOR APA RATED SHEATHING AND APA RATED STURD-I-FLOOR PANELS APA THE ENGINEERED WOOD ASSOCIATION NOTE Panel grade Span Rating Mill number RATED SHEATHING 15/32 INCH 32/16 SIZED FOR SPACING EXPOSURE PRP-108 Thickness Exposure durability classificiation Performance standard Products meeting RATED SHEATHING/CEILING DECK requirements are also designated CEILING DECK ; veneer-faced panels include a face grade in the body of the trademark. Other applicable descriptive data may be included in the area of the trademark near PRP-108 as follows: 1) PS 1-95 All veneer product meeting PS 1 requirements. 2) PS 2-92 Product meeting PS 2 requirements. 3) C-D Veneer-faced Exposure 1 product containing C grade face, D grade back and, in the case of an all-veneer product, containing D grade or better inner plies. 4) C-C All-veneer Exterior product meeting PS 1 requirements for C-C grade. 5) STRUCTURAL I RATED Product meeting the performance requirements of STRUCTURAL I RATED SHEATHING. APA THE ENGINEERED WOOD ASSOCIATION NOTE Panel grade Span Rating Mill number RATED STURD-I-FLOOR 19/32 INCH 20 oc SIZED FOR SPACING T&G NET WIDTH 47-1/2 EXPOSURE PRP-108 Thickness Exposure durability classificiation Performance standard Other applicable descriptive data may be included in the area of the trademark near PRP-108 as follows: 1) PS 1-95 All veneer product meeting PS 1 requirements. 2) PS 2-92 Product meeting PS 2 requirements. 3) UNDERLAYMENT All-veneer product meeting PS 1 requirements for Underlayment grade. 4) C-C PLUGGED All-veneer Exterior product meeting PS 1 requirements for C-C Plugged grade. 71

74 TRADEMARK EXAMPLE FOR APA RATED SIDING PANELS APA THE ENGINEERED WOOD ASSOCIATION NOTE Panel grade Span Rating Mill number RATED SIDING 19/32 INCH 24 oc SIZED FOR SPACING EXTERIOR 000 PRP-108 HUD-UM-40C Thickness Exposure durability classificiation Performance standard All-veneer product meeting 303 Siding requirements may also be designated Rated Siding 303 and include a face grade in the body of the trademark. Other applicable descriptive data may be included in the area of the trademark near PRP-108 as follows: 1) PS 1-95 All veneer product meeting PS 1 requirements. 72

75 APA RESEARCH AND ING APA The Engineered Wood Association s 37,000-square-foot Research Center in Tacoma, Washington is the most sophisticated facility for basic panel research and testing in the world. The center is staffed with an experienced corps of engineers, wood scientists, and wood product technicians. Their research and development assignments directly or indirectly benefit all specifiers and users of engineered wood products.