AC R2 8. ECO-Block, LLC. May 23, ICC Evaluation Service, Inc Workman Mill Road Whittier, California 90601

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1 AC R2 8 May 23, 2007 ICC Evaluation Service, Inc Workman Mill Road Whittier, California Attention: David Pereg, P.E. - Staff Engineer Re: Proposed Acceptance Criteria for Stay-in-place, Foam Plastic Insulating Concrete Form (ICF) Systems for Solid Concrete Walls, Subject AC R2 (DP/RK) ECO-Block, LLC has reviewed the above referenced document and is in full support of the document as written. We look forward to the implementation of this document in order to further advance the Insulating Concrete Form industry. ECO-Block, LLC Sheldon Warman, P.Eng. Technical Director Grader Street, Suite 700 ~ Dallas, TX Tel ~ Fax ~ Toll-Free

2 AC R2 8 May 22, 2007 ICC-ES Evaluation Committee ICC Evaluation Service, Inc Workman Mill Road Whittier, California Reference: Subject: AC353 Proposed Acceptance Criteria for Stay-in-place, Foam Plastic Insulating Concrete Form (ICF) Systems for Solid Concrete Walls (AC R2 (DP/RK) Objections to Proposed Structural Design Provisions Dear Sir or Madam, AC353 as proposed for the June 2007 hearing differs significantly from the proposed acceptance criteria presented at the June 2006 hearing. The cover letter dated May 1, 2007 is misleading when it excluded from the list of technical revisions in its introduction the revisions to the structural design provisions. The structural design provisions described on page 2 of the cover letter do not indicate that a significant revision has been proposed. For convenience of the Committee, the pertinent text from both cover letters, one from the June 2006 hearing and the recent letter for the June 2007 hearing, are presented here for comparison: May 1, 2006 Letter (for the June 2006 hearing): The proposed criteria is applicable to both flat and waffle-grid, solid-wall ICFs complying with IRC dimensional specification, and sets forth material test requirements and design provisions for those ICFs when they are used for construction under the IRC, International Building Code, BOCA National Building Code/1999, 1999 Standard Building Code and the 1997 Uniform Building Code. May 1, 2007 Letter (for the June 2007 hearing): The criteria is applicable to solid, flat wall ICFs complying with IRC dimensional specifications, and sets forth material test requirements and design provisions for those ICFs when they are used for construction under the IRC, the International Building Code (IBC), the BOCA National Building Code/1999 (BNBC), the 1999 Standard Building Code (SBC) and the 1997 Uniform Building

3 May 22, 2007 Page 2 ICC-ES Evaluation Committee June 6, 2007 Public Hearing Comment Submittal AC R2 (DP/RK) Code (UBC). The criteria is also applicable to waffle-grid, solid-wall ICFs complying with IRC dimensional specifications, and sets forth material test requirements and prescriptive design provisions for those ICFs when they are used for construction under the IRC, SBC and UBC. The notable difference is the waffle-grid, solid-wall ICF has been limited to the prescriptive design provisions. If the waffle-grid formed concrete wall design exceeds the applicable limits imposed on the prescriptive provisions there is no allowance to permit the use of the design provisions for concrete walls provided by the IBC and/or ACI 318. This exclusion will effectively prohibit the use of waffle-grid ICFs in large residential structures and non-residential applications. The new limitation imposed on the wafflegrid ICF is throughout the acceptance criteria; specifically in Section 1.2 and Sections , , , , and The following criterion was moved out of Structural Design - Section 3.9 (now Section 3.10). When required by the code official, calculations showing compliance with the general design requirements of Chapter 16, 18 and 19 of the IBC, BNBC or UBC, as applicable, shall be submitted to the code official for approval, except that calculations are not required when the building design is based on Section or of this criteria, or foundation design is based on IRC Section R404 or SBC Section The calculations and details shall be prepared by a registered design professional where required by the statutes of the jurisdiction in which the project is to be constructed. This statement is re-located to Section (Section 6.0 Evaluation Report Recognition) as part of Section 6.1 which states The evaluation report shall include the following information: Although the ESR report may include this wording, the proposed limitation of waffle-grid ICFs to the prescriptive provisions makes it unclear if ACI 318 can be used to design waffle-grid formed walls. The prescriptive provisions of the IRC, the SBC, and the Prescriptive Method for ICFs in Residential Construction (publication #EB118) were based on the design provisions of ACI 318 and/or the IBC. The applicability limits imposed on buildings using ICFs and the prescriptive provisions was necessary to ensure the safe use of ICF formed concrete walls in residential design. If the residential design exceeds the applicability limits or if the project is a non-residential design, the building official should require that project specific calculations be prepared to show compliance with the design requirements of the applicable code. As currently written, AC353 will limit the use of waffle-grid ICFs to residential projects which do not exceed the applicability limits of the prescriptive provisions. There is no engineering justification to exclude the waffle-grid ICF formed solid concrete wall from the design provisions allowed for the flat-wall ICF formed solid concrete wall. The same engineering design provisions used to develop the prescriptive provisions for the flat-wall and waffle-grid ICF formed walls are applicable for nonprescriptive designs.

4 May 22, 2007 Page 3 ICC-ES Evaluation Committee June 6, 2007 Public Hearing Comment Submittal AC R2 (DP/RK) The proposed wording of AC353 in regards to the structural design of waffle-grid ICFs conflicts with or lacks clarity with two current ICC and ICC-ES documents. 1. In the 2006 IRC, Section R404.4 and Section R611.1 state: Insulating Concrete Form (ICF) walls shall be designed and constructed in accordance with the provisions of this section or in accordance with the provisions of ACI 318. When ACI 318 or the provisions of this section are used to design insulating concrete form walls, project drawings, typical details and specifications are not required to bear the seal of the architect or engineer responsible for design, unless otherwise required by the state law of the jurisdiction having authority. 2. A recently issued ICC-ES report for the waffle-grid form eform TM by Reward Wall Systems, ESR 1552 dated January 1, 2007, includes structural provisions for a waffle-grid formed wall. ESR 1552 is in compliance with the 2006 IBC and 2006 IRC. In Section it states: When the eform waffle-grid ICF forms are components of buildings that do not conform to the applicability limits of Sections R and R611.2 of the IRC, or Section and of the SBC, or the structure is regulated by the IBC, BNBC, or UBC, the structural analysis and design of the concrete must be prepared in accordance with ACI 318 and Chapter 19 of the IBC, BNBC, SBC or UBC, as applicable. The structural design professional is responsible to determine the structural adequacy of a flat-wall or waffle-grid formed concrete wall in designs that are residential that exceed the applicability limits of the prescriptive provisions or for non-residential structures. If the building official is concerned for the structural adequacy of a waffle-grid formed concrete wall, they should require that a qualified design professional prepare the calculations and details in accordance with ACI 318. The waffle-grid ICF form has been used successfully for over 30-years in residential and non-residential concrete building construction. American PolySteel requests the Evaluation Committee to instruct the ICC-ES Staff to undo the revisions to the structural design provisions of AC353 to allow both the flat-wall and waffle-grid ICF formed concrete walls the same opportunity to use current code accepted design provisions when the prescriptive provisions are deemed non-applicable. Sincerely, David R. Jarmul, P.E. Director of Engineering American PolySteel, LLC Albuquerque, New Mexico

5 From: Kelvin L Doerr [mailto:kdoerr@rewardwalls.com] Sent: Tuesday, May 22, :19 AM To: Michael Beaton; David Pereg; Kurt Stochlia Cc: djarmul@polysteel.com; Vera Novak ICFA; EJ Parks; EJ Parks; Hank Pfeiffer; Edward L. Storm Subject: June 2007 ICC ES Hearing - AC353 Importance: High Gentlemen, I have noticed that the ICF waffle-grid systems have not been included in the proposed AC353 to be allowed to be designed in accordance to ACI 318. ACI 318 is referenced as the concrete design code in the 2006 IBC and IRC. A previous draft of AC353 allowed waffle-grid ICF walls to be designed in accordance to ACI 318. The most recent draft appears to have eliminated the option of designing waffle-grid ICF walls to ACI 318. This was done silently without any communication between ICC ES and the ICFA. This seems odd as the ICFA and ICC ES had been working closely together to create this AC353 proposal. There is nothing within ACI 318 that would not allow the design of waffle-grid ICF walls. Waffle-grid systems are a solid monolithic concrete wall. They are much different in that regard to screen grid and post and beam concrete walls they are continuously solid. There is no reason to exclude the design of the waffle-grid walls from ACI 318 for the following reasons. 1. ESR-1552, dated January 1, 2007, and in compliance to 2006 IBC and IRC already states that the eform waffle-grid wall can be designed in accordance to ACI Since the waffle-grid wall is a solid concrete wall, one method of design can be accomplished by using the actual cross sectional geometry and using a one foot wall cross section to develop a bending and axial interaction diagram. 3. Back in the late 90s, I visited ICBO along with other industry leaders on the behalf of the limitation of the design of waffle-grid walls to 10 feet. We successfully demonstrated to ICBO (Peter Bahlo and others) that 10 feet should not be a limit as one can design waffle-grid walls to any height according to ACI 318 within the ACI 318 limits, not a 10 foot limit. This situation or issue is no different today. 4. There is simply nothing within ACI 318 that does not permit the design of waffle-grid walls. I don t see anything within the ACI 318 design code that would not allow for design of waffle-grids to ACI 318. Structural engineers are daily always designing concrete structures with different geometries (non-rectangular) and this does not limit them. ACI does not limit solid concrete geometries. Please use this as documentation for support of designing waffle-grid ICFs to ACI 318 and this inclusion within AC353 at the upcoming June 2007 hearing. If you have any questions, please contact me. Thank you in advance for your support. Sincerely, Kelvin Doerr, P.E. AC R2 8

6 AC R2 8 THERMOMASS P.O. Box 950 BUILDING INSULATION SYSTEMS B y Com p o si te Te chnolog ies C o r p o r a tio n Date: 5/23/2007 David Pereg, P.E. Staff Engineer ICC Evaluation Service 5360 Workman Mill Road Whittier, CA Boone, IA D D Re: Proposed AC Stay-in-place Foam Plastic ICF for Solid Concrete Walls Dear Mr. Pereg, We would like to offer the following comments to the proposed AC Line number 11 includes only the material properties of the ICF and their components. We believe that some of the physical properties, especially for waffle grid ICFs, should be included in the evaluation and the report. These physical properties are required to design the walls using IBC or ACI 318. Two of the properties that are required in the design per ACI 318, chapter 14 are effective wall thickness and effective moment of inertia for waffle grid ICF. 2. Line number 71, NFPA should be referenced rather than NFPA since NFPA was approved as the American National Standard on August 18, Line number 136 refers to IRC table R611.4(2) and we do believe that it should reference to table R Section 3.3 Surface Burning Characteristics, Line number 143: Please add "(foam plastic with embedded cross ties)" after the words "foam plastic panels". The reason is that we believe cross-tie inclusion is necessary during ASTM E84 testing. The test specimen should be made of both foam insulation and cross-ties flanges since the surface burning characteristics are different with the cross-ties, which is the intended end use. 5. We believe that "room corner test" is not an optional test per section 3.5 and hence section should be removed from section 3.8 which is an optional requirement. We recommend that section be included in section 3.5 which deals with the thermal barrier. 6. Line number 236 states; "since the thermal barrier is attached to the wall using proprietary methods... " therefore we believe the material properties of the fasteners used to attach the thermal barrier should be listed and tested in Section 3.0. We believe this section should also outline the minimum number of fasteners required to secure the thermal barrier in position. 7. Section : Typically, in ICF construction the electrical outlets and chases are placed directly within field fabricated cavities made in the foam insulation. We recommend that this section include discussion on isolating the plastic foam insulation from electrical components. We also recommend that this section contain discussion on how the creation of air cavities within the foam insulation influence the flame spread characteristics of the ICF. 8. The plastic foam insulation used in ICF construction will begin to soften at 200 F, liquefy at 300 F, and ignite at 650 F. Molten and liquefied plastic are often credited with injuring both the fleeing and the rescuers. We recommend that this issue be addressed in section 3.8 by requiring the details be provided showing how egress points may be constructed to prevent the passage of molten or liquefied plastic insulation during a fire event. D TOLL FREE : D LOCAL: D FAX: D

7 Mr. David Pereg, P.E. May 23,2007 Page 2 of 2 9. Section refers to IBC, UBC or BNBC method for flat ICFs and do not reference that this section is applicable to waffle grid ICFs. If not applicable to waffle grid, an exclusion statement should be added to make it clear. 10. Section refers to Fastener Strength in plastic cross-ties. We believe that ASTM D 1761 which is designed for the mechanical fasteners in wood will not give a representative values for fasteners in the intended application unless modifications are specified. Section refers to lateral strength testing procedure and cites ASTM D In ASTM D 1761, the lateral strength of the fastener is determined by attaching two pieces of wood in lap joint configuration. We believe that this criteria should be more descriptive of performing the testing since ASTM standard is not available for this condition. Similarly, the withdrawal load strength per ASTM D 1761 will not give representative results. We also recommend that a section be added requiring fastener tests in "hot cond ition" since metallic fasteners conduct heat much faster and softens and melts the plastic cross tie flange, thus reducing the capacity of the fasteners considerably. 11. We request ICC-ES to research as to the validity of NFPA 286 for this application. r\ifpa section states that "This method does not provide data that can be generalized to apply to rooms or spaces of different shapes, sizes, and ventilation ". Since the test chamber of NFPA 286 is 12' x 8' x 8' high, and most buildings are much larger than this, will this method predict the true response of the ICF with wall covering? Section 4.3 is titled "Room Corner Fire Test" while the NFPA 286 is for a room of 4 sides and ceiling. NFPA section states "This fire test method is not intended for the evaluation of fire endurance of assemblies, nor is it intended for the evaluation of the effect of fires that originate within a wall assembly" and yet the section of this criteria uses the endurance of the thermal barrier as the acceptable condition. If NFPA 286 is the choice, then suitable modifications to the test method and specimen mounting should be added to the criteria. We recommend that the specimen mounting to the test frame should be before the wall covering are applied and also the wall covering should be mounted about W' above the floor as typically constructed in buildings. This test should also include the PVC electrical outlet box and PVC clad electric wiring which is a common practice in the building industry. 12. Line number : We recommend modifying the sentence to..."a room corner test shall be conducted in accordance with NFPA 286 for each assernbly of cross-tie and fastener for which recognition is sought". We believe this procedure should specify that ICF assemblies with plastic cross-tie flanges be tested and evaluated separately from ICF with steel cross-tie flanges. 13. Section 6.1.3: Since the fasteners are used to install the wall covering to the flanges which is a proprietary method, fastener size, type and manufacturer should be provided in addition to the loads. Sincerely, Composite Technologies Corporation \j~~~fta Venkatesh Seshappa, P.E. & S.E. Director of Engineering