1/18/2009. Continuing Education LEARNING OBJECTIVES. Wood Framing Members. Grade Stamp. Wood Framing Members

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1 Continuing Education Tips From The Trade How to where to find information on specifying Wood Products Brought to you by WoodWorks An Initiative of the Wood Products Council Lisa Podesto, PE Northern California Technical Director Wood Products Council is a Registered Provider with The American Institute of Architects Continuing Education Systems. Credit earned on completion of this program will be reported to CES Records for AIA members. Certificates of Completion for non-aia members are available on request. This program is registered with the AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation. Registration no.. LEARNING OBJECTIVES Wood Framing Members 1. Learn more about proper specification of wood products. 2. Understand what the wood industry is doing to simplify wood specification 3. Learn where to find the information you are looking for. Structural Panels Sawn I-Joists and SCL Grade Stamps and Installation Simplification Unique Products / Alternative Systems Frequently Asked Questions Guide to Resources Wood Framing Members Grade Stamp Structural Panels Sawn Engineered Guide to Resources APA Trademark PLYWOOD or ORIENTED STRAND BOARD Grade Specify Rated Sheathing CBC says either standard is acceptable 1

2 Plywood Grades Grade Stamp A- Smooth, paintable. Not more than 18 neatly made repairs. B- Solid surface. Repairs, and tight knots to 1 inch. Cplugged-Improved C veneer. Knotholes or other open defects limited to 1/4 x 1/2 inch. Thickness C- Tight knots to 1-1/2 inch. Knotholes to 1 inch across grain. Occasional 1-1/2-inch knothole. D- Knots and knotholes to 2-1/2 inch. Occasional 3-inch knothole. Span Rating Span Rating Design Criteria Span Rating Conditions Strength axis perpendicular to supports Roof Span L/ PSF live 10 PSF dead Floor Span L/ PSF live 10 PSF dead Continuous across 2 or more spans Grade Stamp Bond Classifications EXTERIOR EXPOSURE 1 Bond Classification Waterproof glue Minimum C-grade veneer (plywood) Waterproof glue Permit D-grade veneer (plywood) 2

3 Grade Stamp Correct Panel Spacing Panel clip or tongue-andgroove edges if required 1/8" spacing APA RATED SHEATHING Stagger ends (optional) Spacing req. built in Protect edges of Exposure 1 panels, or use Exterior panel starter strip APA Panel Wall Sheathing Other things you may see 1/8" spacing APA RATED SHEATHING Filler strip if required 8" minimum clearance What is wrong with this picture? Grain is parallel to supports Sheathing Too Narrow 24 Min. Width or Blocked (Tech Note R275) Wood Structural Panel Challenges Challenges Solution 82 + species of wood introduction of span ratings 2 different standards 10 grades and thicknesses Sheathing or Single Floor For Sturd-I-Floor applications For diaphragms Shear wall and diaphragm 12 grades, span ratings and construction thicknesses roof sheathing Multiple thicknesses shear wall 3

4 Energy Efficient Products Cost effective systems Structural Insulated Panels 8 x24 jumbo panels available Faster erection time Higher R values OSB Radiant Barrier Panels Blocks up to 97% of radiant heat Cost premium ~ $ $0.10/sf more than traditional OSB Pre-framed Roof Panels 8-10 segments assembled on the ground and lifted into place Panel can be installed parallel or perpendicular to framing Advantages Speed of erection Cost savings Jobsite safety Cost effective systems Wood Framing Members Lapped Sheathing Reduces hardware for uplift and overturning Blocking is required at panel edges Offer this as a detail option Works well in conjunction with perforated shearwall method Structural Panels Sawn Engineered Guide to Resources WWPA Grade Stamps GRADE MARKS: a) WWPA Certification mark b) Mill Identification c) Grade designation d) Species identification Challenges 7 grading agencies BASIC INFORMATION FROM STAMP: 1. Who made it 2. How strong is it e) Condition of seasoning MC-15 15% max. MC KD-15 S-DRY - 19% max. MC KD S-GRN - over 19% MC (unseasoned) 31 species excluding Southern pine 8 grades for each species 248 species/grade options 6 different thicknesses for dimension lumber 10 different widths for dimension lumber 3000 different possible bending stresses 4

5 Solutions Stress grade classification similar to what is used in other countries such as Europe 9 classes designated as: C35, C30, C27, C24, C22, C20, C18, C16, C14 C18, C24 and C30 are the dominate grades specified Create a family of primary product designations Select Structural, No. 1, No. 2, No. 3 with no species distinction Several U.S. lumber grading agencies are evaluating these and other options Frequently Asked Question What is the difference between SPF and SPF south DF-L and DF-L(N) HF and HF(N) SPF is a Canadian Species, SPF (S) is a US species DF-L (N)and HF (N) is produced in Canada where DF-L and HF is produced in the US Stud Walls For walls over 10 prescriptive tables not applicable. Engineering is required. 2x4, 3x4, 2x6 & 2x8 When wall framing exceeds 20 in height special orders may be required. Rule of thumb NDS has slenderness requirement for studs (l/d<50). For a load bearing 2x4 L < 14-7 ALWAYS Stud Walls Options for Strait Tall Walls Kiln dried framing lumber Engineered wood Laminated strand lumber (LSL), Oriented Strand (OSL), etc. Finger Jointed Sawn Frequently Asked Question How is a fire wall constructed per CBC with the new language regarding sufficient structural stability? 2006 IBC commentary detailing continuous diaphragm SEAoSC Light Framing Construction Committee Seismology Opinion on Continuity of Plywood Diaphragm Sheathing in 2 hr and 3hr Fire Walls Finger Jointed Sawn Sawn lumber - Approved end-jointed lumber is permitted to be used interchangeably with solid-sawn members of the same species and grade. Note HRA for 1 hr walls 5

6 Finger Jointed Sawn Machine Stress-Rated (MSR) WWPA Portals/9/docs/PDF/F F-HRA.pdf GRADE STAMP Product Designation MSR, MACHINED RATED Registered Trademark of Grading Agency Mill Number or Name Moisture Content Species Fb and E rating When additional control process are implemented Ft, SG, Fc perp and Fv Machine Stress-Rated (MSR) Dimension evaluated by mechanical stress rating equipment Non-destructively evaluated Bending Stiffness Sorts by Modulus of Elasticity Visual requirements MSR lower variability in strength MSR lumber properties are species independent Not widely used (limited availability) Mostly used for engineered wood or wood trusses Frequently Asked Question Where can I find information on adhesives used in wood construction? Wood Engineering and Construction Handbook published by McGraw Hill (Chap. 12) Evaluation, Maintenance and Upgrading of Wood Structures published by ASCE (Chap. 5) Frequently Asked Question Where can I find information on evaluation, maintenance and repair of existing structures? Wood and Timber Condition Assessment Manual West Coast Inspection Bureau does grades existing timbers Handy Resource for Many FAQ Forest Products Laboratory Wood Handbook Where can I find information to determine the species/grade of a existing wood framing member? What factors affect wood finish performance? How do I prevent finish failure/discoloration? What is the difference between fire retardant treatment and fire retardant coatings? 6

7 Handy Resource for Many FAQ Wood Framing Members Western Wood Preservers Institute How is treated wood disposed of in California? Are there reductions in structural values for fire retardant treated wood? What treatments are suggested for environmentally sensitive areas? Can treated wood be recycled as fuel? Structural Panels Sawn Engineered Guide to Resources Glue Laminated Features & Applications Glulam: Wood laminations bonded together Wood grain runs parallel to the length Dispersal of strength reducing characteristics Glue Laminated Timber Typical Widths: 2-1/2" to 10-3/4" Laminations: 1-3/8" for Southern Pine 1-1/2" for other Camber Camber TOP L = Span (ft) Stock Beams 0 Radius 3,500 ft Industry Recommendations Floor 1.0 x DL x Roof 1.5 x DL x L = Span (ft) = Camber (in) Radius of Curvature (ft) 3500 Ft. Radius = Western 2000 Ft. Radius = Southern = Camber (in) Radius of Curvature (ft) 7

8 Handy Resource for Many FAQ American Institute of Timber Construction How do you calculate the fire resistance of glulam timbers? How is checking addressed in glulam timbers? How is a tudor arch designed? How do you inspect, maintain and repair glulam timbers? Alternative to Preservative Treatment Alaska Yellow Cedar Western Red Cedar Port Orford Cedar Treated Glulams both before and after manufacture Manufacturing Balanced vs. Unbalnaced Manufacturing TOP Unbalanced Simple Spans No. 2D No. 2 No. 2 Balanced Continuous Spans or Cantilevered TL No. 2 No. 2 Cantilevered Span Glulam No. 3 No. 3 Simple Span Glulam No. 2 No. 1 TL TL=Tension Lamination No. 2 No. 1 TL TOP Stamp What is wrong with this picture? 8

9 Cost Effective Product Glulam with LVL Tension Lamination LVL Tension Lam Full length- no finger joints Greater tensile strength = 3000 psi Challenges 50 Glulam Bending Stress combinations tabulated in the 2005 NDS 51 Glulam Axial Load combinations in the 2005 NDS Solution Simplified Table of 7 stress class combinations in the 2005 NDS NDS Stress Classes Stress Class Fb MOE Fv 16F-1.3E ,300, F-1.5E ,500, F-1.7E ,700, F-1.8E ,800, F-1.9E ,900, F-2.1E ,100, F-2.1E ,100, Use of a Glulam Stress Class Stress Class Western Species Southern Pine Unbalanced Balanced Unbalanced Balanced 16F-1.3E 16F-V1 (DF/SW) 16F-V6 (DF/DF) 16F-V2 (SP/SP) 16F-V5 (SP/SP) 16F-V2 (HF/HF) 16F-V7 (HF/HF) 16F-V3 (SP/SP) 16F-E3 (SP/SP) 16F-V3 (DF/DF) 16F-E1 (SP/SP) 16F-V4 (DF/SW) 16F-E1 (SW/SW) 16F-E2 (HF/HF) 16F-E3 (DF/DF) 20F-1.5E 20F-V3 (DF/DF) 20F-V7 (DF/DF) 20F-V2 (SP/SP) 20F-V5 (SP/SP) 20F-V4 (DF/DF) 20F-V8 (DF/DF) 20F-E1 (SP/SP) 20F-E3 (SP/SP) 20F-V10 (DF/HF) 20F-V9 (HF/HF) 22F-V1 (SP/SP) 22F-V5 (SP/SP) 20F-V12 (AC/AC) 20F-V13 (AC/AC) 22F-V2 (SP/SP) 22F-E3 (SP/SP) 20F-E2 (HF/HF) 20F-E6 (DF/DF) 22F-V3 (SP/SP) 20F-E3 (DF/DF) 20F-E7 (HF/HF) 22F-V4 (SP/SP) 20F-E8 (ES/ES) 22F-V8 (DF/DF) 22F-E1 (SP/SP) 22F-V3 (DF/DF) 22F-V10 (DF/DFS) Commonly used for floor and roof framing Long lengths readily available Flange: LVL Web: OSB Plywood I-Joist Flange Widths: 1-1/2" to 3-1/2" Up to 30 Deep Can be manufactured with FSC Challenges Over 400 I-Joists grades, just for commercial applications (20 30 depths) Each manufacturer has an evaluation report with design data and installation recommendations (ICC-ESR) Solution APA proposes simplification similar to specification for residential applications with PRI-400 9

10 Commercial I-Joist Series C1 1-1/2 X 2-1/2, 24F-2.0E flange Depths from 11-7/8 to 20 C2 1-1/2 X 3-1/2, 24F-2.0E flange Depths from 11-7/8 to 20 C3 2-1/8 x 3-1/2, 24F-2.0E flange Depths from 14 to 30 C4 3 x 3-1/2, 28F-2.3E flange Depths from 14 to 30 Structural Composite PSL LSL LVL OSL Features & Applications Product Basics Laminated Veneer (LVL): Produced by bonding thin veneers together Used for beams, headers, rafters & scaffold planking The grain of all veneers is parallel to the long direction Common Thicknesses: 3/4" to 3-1/2" Parallel Strand (PSL): Manufactured from veneers clipped into long strands in a parallel formation and bonded together Strand length-to-thickness ratio is around 300 Used for headers and beam as well as columns. Laminated Strand (LSL): Similar to PSL. Flaked strand length-tothickness ratio is around 150 Used for a variety of applications from studs to millwork components Product Basics Product Basics Oriented Strand (OSL): Similar to LSL. Flaked strand length-tothickness ratio is around 75 Used for a variety of applications from studs to millwork components 10

11 LSL Tested Fire Assembly Material Grades for Structural Composite (SCL) Challenges Laminated veneer lumber (LVL) - 85 grades + Oriented strand lumber (OSL) - 8 grades + Parallel Strand lumber (PSL) - 16 grades + Laminated Strand (LSL) - 8 grades + Total grades + Frequently Asked Question Solution PRL 501: APA Introduced a Performance Std. for LVL Goal is to develop similar performance stds for Non Residential applications 1.5E, 1.9E, 2.1E Five Stress Grades 1.5E 2250F 1.8E 2600F 1.9E 2600F 2.0E 2900F 2.1E 3100F Where can I get information for engineered wood specifications? Engineered Wood Construction Guide published by APA Wood Framing Members APA (Engineered Wood Assoc.): Structural Panels Sawn Engineered Guide to Resources www2.wwpa.org

12 1/18/2009 APA resource: American Wood Council (AF&PA): AWC resource: Western Wood Products Assoc.: www2.wwpa.org Canadian Wood Council: WoodWorks: 12

13 Thank you!! WoodWorks! Michelle Kam-Biron, S.E