August 1, 2018 PARTIES INTERESTED IN PREFABRICATED, COLD-FORMED STEEL, LATERAL-FORCE-RESISTING VERTICAL ASSEMBLIES

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1 August 1, 2018 TO: PARTIES INTERESTED IN PREFABRICATED, COLD-FORMED STEEL, LATERAL-FORCE-RESISTING VERTICAL ASSEMBLIES SUBJECT: Proposed Revisions to the Acceptance Criteria for Prefabricated, Cold- Formed Steel, Lateral-Force-Resisting Vertical Assemblies, Subject AC R2 (WG/SF) Dear Colleagues: The subject acceptance criteria was posted for comment on our website on the February 1, 2018 alternative criteria process. We received comments from the American Iron and Steel Institute (AISI), MiTek USA, Inc. and Simpson Strong-Tie Company, Inc. These comments are attached to this letter, and were used in formulating the proposed revisions. We are seeking your comments on these proposed revisions as presented in the enclosed draft. The revisions, which are being posted on the ICC-ES web site for 30 days of public comment, may be summarized as follows: 1. Add references to the 2018 International Building Code (IBC) and International Residential Code (IRC) and its referenced standards. 2. Add provisions to address the AISI S400 requirements for non-designated energy dissipating mechanisms (non-dedms) in a proposed new Section 4.5. While the Evaluation Committee will be voting on the revised criteria during the 30- day comment period, we will seriously consider all comments from the public and will pull the criteria back for reconsideration if public comments raise major issues. In that case, we would seek a new committee vote; further revise the draft and post it for a new round of public comments; or put the revised criteria on the agenda for a future Evaluation Committee hearing. If they are of interest, please review the proposed revisions and send us your comments at the earliest opportunity. At the end of the 30-day comment period, we will post on our web site the correspondence we have received and, in memo form, the responses of our technical staff.

2 AC R2 2 To submit your comments, please use the form on the web site and attach any letters or other materials. If you would like an explanation of the alternate criteria process, under which we are soliciting comments, this too is available on the ICC-ES web site. Please do not try to communicate directly with any Evaluation Committee member about a criteria under consideration, as committee members cannot accept such communications. Thank you for your interest and your contributions. If you have any questions, please contact me at (800) , extension You may also reach us by at es@icc-es.org. Yours very truly, WG/raf Encl. cc: Evaluation Committee William Gould, P.E. Vice President

3 March 2, 2018 Jon-Paul Cardin, P.E. Codes and Standards Engineer 120 South 2 nd Street Coeur d Alene, ID Dear Mr. Zhao: The following comments are in reference to the Proposed Revisions to the Acceptance Criteria (AC322) for Prefabricated, Cold-Formed Steel, Lateral-Force-Resisting Vertical Assemblies, as released for public comment. 1. Nominal shear strength of SFRS (V n ): Nominal strength of a SFRS, Vn, shall be 2.5 times the ASD in-plane shear strength, P ASD, determined in accordance with Section AISI Comment: Nominal strength should be the direct result from the tested assembly. Phi or omega factors should be applied after the determination of the nominal strength, and should not be a fixed number. The phi or omega factor will vary based on test data. 2. Expected shear strength of SFRS (Ω E V n ): Expected shear strength of a SFRS, Ω E V n, shall be equal to the overstrength factor, Ω 0, as listed in ASCE/SEI 7-16 Table , Items A.15 and A.16, times the nominal shear strength, V n. AISI Comment: AISI S400 Supplement 1 provides further guidance for the Ω E factor. There are different paths and approaches for different systems based on knowledge of the energy dissipating system. AISI recommends that AC322 directs the user to AISI S400 for consideration of the expected strength factor. 3. Required strength (R u ) of non-dedm: Considering all applicable limit states and failure modes, how should the required strength (R u ) of non-dedm based on expected strength of SFRS, Ω E V n, be determined? AISI Comment: The required strength of non-dedm is determined based on the mechanics and configuration of the system. 4. Available strength ( R n ) of non-dedm: Considering all applicable limit states and failure modes, how should the available strength, R n, of non-dedm be determined? Should the available strength be based on calculations per code provisions, static and /or cyclic testing, or a combination of calculations and testing? AISI Comment: There are multiple acceptable methods for determining the available strength of non-dedm in a system. Those include code based calculations, testing and a combination of both. AISI S100 provides provisions regarding those methods.

4 5. Conditions of acceptance for non-dedm: For each non-dedm element of the SFRS, considering all applicable limit states, available strength, R n, shall be greater than or equal to corresponding required strength, R u. AISI Comment: Note that both the overstrength factor, Ω 0, and the expected strength factor, Ω E, must be considered in evaluation of the required strength. AISI is deeply interested in addressing the topic of establishing design strengths of cold-formed steel SFRS and system components based on testing. The AISI Committee on Framing Standards (COFS) is actively working on better understanding these systems and their behavior under loading conditions. As the COFS learns more about these systems, many of the associated factors and the analysis may be change. AISI has a plan to move forward on this topic and address the analysis within the AISI specifications. Thank you for your consideration. Please feel free to contact me with any questions or concerns regarding this information. Sincerely, Jon-Paul Cardin, P.E. Codes and Standards Engineer Steel Market Development Institute a business unit of AISI 120 South 2 nd Street Coeur d Alene, ID tel: SMDI Construction Market Council Members: AK Steel Corporation ArcelorMittal Dofasco ArcelorMittal USA LLC Nucor Corporation SSAB Americas United States Steel Corporation

5 02 March 2018 Mr. David Zhao Principal Structural Engineer ICC-Evaluation Services 5360 Workman Mill Road Whittier, CA Re: Proposed Revisions to the Acceptance Criteria for Prefabricated, Cold-Formed Steel, Lateral-Force-Resisting Vertical Assemblies, Subject AC R1 (DZ/WG) Dear Mr. Zhao, This letter is in response to ICC-ES request for comments on proposed changes to AC322; posted on the ICC-ES website as part of the Alternative Criteria Development Process. As noted in your letter dated February 1, 2018, the posting of AC322 is currently for comments only for consideration for future posting or committee hearing. In general, I believe there is full support for updating AC322 to reference the 2018 IBC, including the appropriate referenced standards. However I don t believe that the addition of Section 4.5 as proposed, is required to comply with AISI S Please consider the following comments to the questions and comments posed in your February 1 st posting: Addition of Section 4.5 Requirements - From the background provided in your letter, it appears that the basis for ICC-ES proposed changes to AC322 are Sections E and E of AISI The purpose of these sections is to ensure the development of a ductile limit state within a code defined shear wall that uses coldformed steel studs and boundary elements, sheathed with plywood (E1) or light-gage steel sheets (E2). In either case, the ductile mechanism is expected to be shear yielding, through the connection of the sheathing to the wall members or through the sheathing itself. Since the capacities of these systems are predicated on this mechanism, AISI has added sections E and E as design requirements for other elements within the wall system (for example boundary stud packs) so that the shear walls can reliably develop the desired mechanism(s). Items #1 and #2 - Proposed Items 1 and 2 appear to be an attempt to use the requirements of E and E , which are developed specifically for the code defined shear wall systems described, and apply them to lateral force resisting assemblies tested and evaluated under AC322. This appears to be an incorrect application of the specific requirements of E1 and E2 systems as LFRVAs evaluated under AC322 are very likely to have energy dissipating mechanisms that significantly differ from that of the cold-formed steel shear walls. For example, the energy dissipating

6 mechanism of the tested assembly may be flexural yielding of the assembly or yielding (flexural or shear) of an element within the assembly. For those cases, the capacity of the remaining elements of the assembly to develop the required action are already made evident within the test and performance requirements of AC322. Items #3, #4, & #5 It is recognized that elements within a LFRVA need to work together to reliably develop the primary yielding mechanism(s) defined for the system. Furthermore engineering analysis procedures must consider governing limit state(s) in predicting capacities. Such defining mechanisms and analysis procedures are specifically derived from assembly tests; tests defined currently within AC322. As to the required strength of the lateral force resisting elements within the LFRS, but outside of the Assemblies evaluated under AC322, the IBC and referenced material standards already adequately address. Therefore, the addition of these items is not supported. Please do not hesitate to call me if there are any questions regarding these comments or if you would like to discuss the above further. Thank you for your consideration. Regards, Jesse Karns, P.E., S.E. Director of Engineering Lateral Systems MiTek MiTek USA, Inc jkarns@mii.com

7 March 02, 2018 David Zhao, P.E., S.E. Principal Structural Engineer ICC Evaluation Service, Inc. Los Angeles Business/Regional Office 5360 Workman Mill Road Whittier, CA (800) x3722 Subject: Proposed Revisions to the Acceptance Criteria for Prefabricated, Cold-Formed Steel, Lateral-Force-Resisting Vertical Assemblies, Subject AC R1 (DZ/WG) Dear Mr. Zhao, This letter is in response to Proposed Revisions to the Acceptance Criteria for Prefabricated, Cold- Formed Steel, Lateral-Force-Resisting Vertical Assemblies, Subject AC R1 (DZ/WG). As a clarifying point, we would request that language be added to proposed AC322 Section 4.5 stating that the new provisions are applicable only to buildings or other structures framed from cold-formed steel members. In addition, we d also like to address Designated Energy-Dissipating Mechanisms (DEDMs) as they relate to cold-formed steel prefabricated shearwall assemblies evaluated in accordance with AC322 and AC436. AISI S400-15/S1-16, as referenced in the 2018 IBC, states that energy dissipating mechanisms are determined primarily based on test observations and experimental results. Historical full-scale cyclic test observations of cold-formed steel prefabricated shearwall assemblies have shown that multiple energy-dissipating mechanisms are present including, but not limited to: local flange buckling, lateral torsional buckling of the assembly and base plate flexure. As such, our interpretation of AISI S400 provisions indicates that the only structural element directly transmitting load to/from the prefabricated panel that must be designed for expected shear strength of the SFRS, i.e., non-dedm, is the collector element. It should be noted that while the panel anchorage and collector connection are also defined as non- DEDMs, full-scale cyclic testing in accordance with AC322 and AC436 inherently demonstrates that the strength of these elements is sufficient to drive the energy-dissipating mechanisms of the SFRS to their full intended function. As such, the intent of AISI S400 is satisfied and the connection to the collector and anchorage need not consider amplified loads in their design. With respect to the proposed revisions for which you are specifically seeking input, see the following items: Item 1: Nominal shear strength of SFRS (Vn): Nominal strength of a SFRS, Vn, shall be 2.5 times the ASD in-plane shear strength, PASD, determined in accordance with Section SST Response: We agree that nominal strength of a SFRS, Vn, shall be taken as 2.5 PASD where PASD is determined in accordance with AC322 Section This definition is in accordance with AISI S400 Section B3.1 and is substantiated by AISI S400 Section E commentary. Simpson Strong-Tie Company Inc W. Las Positas Boulevard Pleasanton, CA Phone: Fax:

8 Item 2: Expected shear strength of SFRS (ΩEVn): Expected shear strength of a SFRS, ΩEVn, shall equal to the overstrength factor, Ωo, as listed in ASCE/SEI 7-16 Table , Items A.15 and A.16, times the nominal shear strength, Vn. SST Response: We agree that expected shear strength of a SFRS shall be taken as ΩoVn. This definition is in accordance with AISI S400 Sections B3.3 and E1.3.3 and is further substantiated by their associated commentaries. Item 3: Required strength of non-dedm (Ru): Considering all applicable limit states and failure modes, how should the required strength (Ru) of non-dedm based on expected strength of SFRS, ΩEVn be determined? SST Response: AISI S400 appears to provide sufficient guidance on this topic in Sections B3.4 and E which is expanded upon in their associated commentaries. An excerpt from Section B3.4 defines required strength requirements as follows: for all structural members and connections in the lateral-force-resisting system that are not part of the designated energy-dissipating mechanism, the required strength shall be determined from the expected strength of the seismic-force-resisting system, but need not exceed the seismic load effect including overstrength Provisions to determine the required strength of non-dedms not addressed through full-scale cyclic testing would then be added to AC322 Section 4.5 as follows: Required strength for non-dedms may be taken as the lesser of the following options: 1. Ru = ΩoVn = 2.5 Ωo PASD [Conservative and determined from published data]. 2. Ru = Maximum demand shear load from load combinations that include E, with E increased by Ωo. Item 4: Available strength of non-dedm (φrn): Considering all applicable limit states and failure modes, how should the available strength, φrn, of non-dedm be determined? Should the available strength be based on calculations per code provisions, static and /or cyclic testing, or a combination of calculations and testing? SST Response: Based on the previous non-dedm discussion, the available strength (φrn or Rn/Ω) for non-dedms not already evaluated through full-scale cyclic prefabricated panel assembly testing, i.e., the collector element, shall be determined in accordance with AISI Section E , and requires that the available strength be greater than or equal to the required strength (Ru). With respect to available strength, we would suggest that calculations in accordance with code provisions are sufficient to satisfy this requirement, particularly if we are considering only member design with a defined required demand. Simpson Strong-Tie Company Inc W. Las Positas Boulevard Pleasanton, CA Phone: Fax:

9 Item 5: Conditions of acceptance for non-dedm: For each non-dedm element of the SFRS, considering all applicable limit states, available strength, φrn, shall be greater than or equal to corresponding required strength, Ru. SST Response: We agree with the proposed conditions of acceptance, however, we d request that provisions for both ASD and LRFD be included in the new AC322 section(s). In addition, non-dedms for which amplified design is required shall be defined or otherwise identified in the manufacturers evaluation report in order to facilitate design. Lastly, with respect to proposed AC322 Section 4.5, we would recommend that only conditions and/or provisions required to enable the designer to satisfy code provisions for applicable non- DEDMs be included; most notably content in responses to Items 3 and 5 in this letter. Thank you for the opportunity to comment on the proposed revisions to AC322. Please contact me at jellis@strongtie.com or call me at with any questions or comments. Sincerely, Simpson Strong-Tie Company Inc. Jeff Ellis, P.E., S.E., SECB Director of Codes & Compliance d/w: CK, SP, EM Copies:. Steve Pryor, Simpson Strong-Tie Emory Montague, Simpson Strong-Tie Brandon Chi, Simpson Strong-Tie Travis Anderson, Simpson Strong-Tie Caleb Knudson, Simpson Strong-Tie Simpson Strong-Tie Company Inc W. Las Positas Boulevard Pleasanton, CA Phone: Fax:

10 (800) (562) A Subsidiary of the International Code Council PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR PREFABRICATED, COLD-FORMED STEEL, LATERAL-FORCE- RESISTING VERTICAL ASSEMBLIES AC322 Proposed August 2018 Previously approved October 2016, January 2013, October 2009, October 2007 (Previously editorially revised February 2015, March 2014) PREFACE Evaluation reports issued by ICC Evaluation Service, LLC (ICC-ES), are based upon performance features of the International family of codes. (Some reports may also reference older code families such as the BOCA National Codes, the Standard Codes, and the Uniform Codes.) Section of the International Building Code reads as follows: The provisions of this code are not intended to prevent the installation of any materials or to prohibit any design or method of construction not specifically prescribed by this code, provided that any such alternative has been approved. An alternative material, design or method of construction shall be approved where the building official finds that the proposed design is satisfactory and complies with the intent of the provisions of this code, and that the material, method or work offered is, for the purpose intended, at least the equivalent of that prescribed in this code in quality, strength, effectiveness, fire resistance, durability and safety. ICC-ES may consider alternate criteria for report approval, provided the report applicant submits data demonstrating that the alternate criteria are at least equivalent to the criteria set forth in this document, and otherwise demonstrate compliance with the performance features of the codes. ICC-ES retains the right to refuse to issue or renew any evaluation report, if the applicable product, material, or method of construction is such that either unusual care with its installation or use must be exercised for satisfactory performance, or if malfunctioning is apt to cause injury or unreasonable damage. Acceptance criteria are developed for use solely by ICC-ES for purposes of issuing ICC-ES evaluation reports. Copyright 2018 ICC Evaluation Service, LLC. All rights reserved.

11 PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR PREFABRICATED, COLD-FORMED STEEL, LATERAL-FORCE-RESISTING VERTICAL ASSEMBLIES (AC322) 1.0 INTRODUCTION 1.1 Purpose: The purpose of this criteria is to establish requirements for lateral (seismic and wind) racking loads and deflections on prefabricated, coldformed steel (CFS), lateral-force-resisting (LFR) vertical assemblies, including vertical load-carrying elements, to be recognized in an ICC Evaluation Service, LLC (ICC- ES), evaluation report under the 2018, 2015, 2012, 2009 and 2006 International Building Code (IBC) and 2018, 2015, 2012, 2009 and 2006 International Residential Code (IRC). The reason for this criteria is that the codes do not provide necessary provisions which can be used to establish code compliance for products covered in this criteria. The bases of recognition are IBC Section Data on file for existing evaluation reports previously evaluated under the January October (editorially revised February 2015) edition of this criteria is deemed to comply with the August October version of this criteria. Data submitted after August October shall be in compliance with this version of this criteria. 1.2 Scope: This criteria applies to prefabricated, coldformed steel, lateral-force-resisting, load bearing and nonload bearing wall assemblies used in conjunction with light-frame wood or cold-formed steel construction to resist lateral, vertical and transverse loads This criteria references AC436, which defines prefabricated CFS LFR wall assemblies as prefabricated LFRVAs and provides provisions for evaluating seismic equivalency. AC322 is an example of a product-specific acceptance criteria noted in AC436. This criteria includes provisions for evaluation of resistance of prefabricated CFS LFR wall assemblies to in-plane seismic loads with or without superimposed axial (or vertical) compression loads (such as gravity loads), and to in-plane wind loads with or without superimposed vertical compression loads. Additionally, this criteria also includes provisions for evaluation of resistance of prefabricated CFS LFR wall assemblies to vertical loads and out-of-plane loads (transverse loads). 1.3 Codes and Referenced Standards: Where standards are referenced in this criteria, these standards shall be applied consistently with the code upon which compliance is based. Table 1 lists the standards editions that are applicable to each code edition , 2015, 2012, 2009, and 2006 International Building Code (IBC), International Code Council , 2015, 2012, 2009 and 2006 International Residential Code (IRC), International Code Council AISI S100, North American Specification for Design of Cold-formed Structural Steel Members, American Iron and Steel Institute AISI S24000, North American Standard for Cold-formed Steel Structural Framing General Provisions, American Iron and Steel Institute AISI S400-15/S1-16, North American Standard for Seismic Design of Cold-Formed Steel Structural Systems, American Iron and Steel Institute AISI-NAS, North American Specification for the Design of Cold-formed Steel Structural Members (2001), with Appendix A, and 2004 Supplement, American Iron and Steel Institute ASCE/SEI 7, Minimum Design Loads for Buildings and Other Structures, American Society of Civil Engineers ASTM E2126, Standard Test Methods for Cyclic (Reversed) Load Test for Shear Resistance of Vertical Elements of the Lateral Force Resisting Systems for Buildings, ASTM International ICC-ES Acceptance Criteria for Establishing Seismic Equivalency To Code-Prescribed Light-Frame Shear Walls Sheathed With Wood Structural Panels Rated For Shear Resistance Or Steel Sheets (AC436). 1.4 Definitions: The definitions in this section and in AC436 Section 1.4 are applicable to this criteria, except that LFRVAs of Alternative Light-frame Construction noted in Section of AC436 is outside the scope of this criteria Prefabricated Shear Resisting Assembly (PSRA): An assembly consisting of a single structural unit, the integral parts of which are constructed or assembled prior to incorporation into the building structure and designed to resist in-plane lateral shear Composite Shear Resisting Assembly (CSRA): An assembly consisting of a prefabricated shear resisting assembly, with a field connection to a structural member, such as a header, such that the LFR performance depends on the prefabricated assembly and the attached structural member Structural System Type Definition: The assembly evaluated under this criteria shall be defined as one of the following: Frame: As defined in Section 11.2 of ASCE/SEI Shear Wall: A non-perforated structural assembly that resists lateral forces, in the plane of the wall, using the in-plane shear resistance of an attached structural plate. Axial forces and overturning forces in the plane of the wall and lateral forces perpendicular to the wall are primarily resisted by independent framing members attached to the structural plate Designated Energy Dissipating Mechanism (DEDM): Selected portion of the seismic force-resisting system (SFRS) designed and detailed to dissipate energy Non-Designated Energy Dissipating Mechanism (Non-DEDM): Portions of the SFRS that are not designated as DEDM, and are designed and detailed to remain elastic. Page 2 of 6

12 PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR PREFABRICATED, COLD-FORMED STEEL, LATERAL-FORCE- RESISTING VERTICAL ASSEMBLIES (AC322) 2.0 BASIC INFORMATION 2.1 Testing Laboratories: Testing laboratories shall comply with Section 2.0 of the ICC-ES Acceptance Criteria for Test Reports (AC85) and Section 4.2 of the ICC-ES Rules of Procedure for Evaluation Reports. 2.2 Test Reports: Test reports shall comply with AC85 and Section 2.2 of AC Product Sampling: The prefabricated LFR assemblies shall be sampled in accordance with Section 3.1 of AC85. The testing laboratory shall verify the construction of the test assemblies in accordance with Section 3.3 of AC85. Verification shall also be provided that the components of the test assemblies comply with the quality control documentation system addressed in Section 6.0 of this criteria. 3.0 ASSEMBLY INFORMATION 3.1 General: The description shall include the following information: Dimensions: The width, height and length for each assembly type. Assembly: A complete description of the prefabricated assembly elements and material specifications, including DEDMs and Non-DEDMs. 3.2 Connections: Connections shall be detailed or adequately described. Mechanical fasteners and welds shall be properly specified, including fastener type, size, length and location. Assemblies shall be constructed with fasteners having approved values. 3.3 Miscellaneous Assembly Information: Field Modification of Assemblies: Field modification of the assemblies for openings in the sheathing or framing elements is not permitted beyond what was specifically tested Structural Field Connections: Structural connections between the prefabricated assembly and the structure, necessary for installation of the assembly, made in the field at the time of installation, shall be consistent with the intent of this criteria. 4.0 TEST AND PERFORMANCE REQUIREMENTS 4.1 General: To be evaluated under this criteria, all assemblies and support conditions must be tested and analyzed as described in this section (Section 4.0). Assemblies and support conditions to be recognized in an evaluation report shall be limited to the sizes and materials used in the tests unless recognition is based on data interpolation in accordance with Section No substitution of materials is allowed unless permitted by ICC-ES For each LFRVA configuration, engineering analysis shall be in accordance with Sections 4.2 and 4.5 to predict the assembly s structural capacities, including resistance to in-plane lateral load, vertical load, and transverse load; in-plane cyclic shear testing shall be in accordance with Sections 4.3 to establish seismic equivalency to code-prescribed light-frame shear walls sheathed with wood structural panels, and to determine resistance to in-plane lateral (seismic and wind) load with or without vertical loads. Data analysis shall be in accordance with Section 4.4. Page 3 of Under this criteria, the products are expected to conform to conditions noted in AC436, Section 3.1.2, Item a, and potentially Items b and d, and thus are required to conform to AC436, Sections and by engineering analysis/supplemental cyclic in-plane lateral shear testing with superimposed vertical loads. As directed by Section of AC436, supplemental cyclic in-plane lateral shear testing with superimposed vertical loads, if required by Section or of this criteria, does not need to satisfy the seismic equivalency requirements of this criteria When the products conform to conditions noted in AC436, Section 3.1.2, Item a or Item b, engineering analysis/supplemental testing shall conform to AC436, Section 3.1.4, Option (1), which requires engineering analysis alone, or Option (3), which requires combined engineering analysis and supplemental cyclic in-plane lateral shear testing with simultaneously applied vertical loads When the products conform to conditions noted in AC436, Section 3.1.2, Item d, engineering analysis/supplemental testing shall conform to AC436, Section 3.1.4, Option (3), which requires combined engineering analysis and supplemental cyclic in-plane lateral shear testing with simultaneously applied vertical loads. 4.2 Engineering Analysis: Engineering analysis shall be in accordance with the IBC and its referenced standards as noted in Section 1.3 of this criteria. Special emphasis must be placed on requirements on analysis noted in IBC Section and all applicable limit states noted in the referenced standards Under this criteria, it is necessary for the requirements noted in AC436, Section , to be satisfied, so that the engineering analysis can be used to predict an assembly s structural capacities, including resistance to gravity loads, out-of-plane loads, and combined gravity loads and in-plane lateral loads. 4.3 In-plane Cyclic Shear Load Tests: Testing shall be in accordance with AC436 Section 4.0, except with modifications noted in this section Test Setup: Cyclic shear tests shall be conducted on test assemblies with boundary conditions that are reflective of the intended use, as noted in this section Foundation-on-grade: Assemblies intended to be installed on a foundation-on-grade condition shall be tested on a rigid base First-floor Raised Floor: Assemblies intended to be installed on the first floor of a structure with a crawl space foundation shall be tested by placing the walls over a representative floor system constructed on a rigid base Second Floor: Assemblies intended to be installed in the second floor of a structure (or higher) shall be tested by placing the assemblies on a representative floor system constructed over a representative wall system, all of which is supported by a rigid base. The representative wall system supporting the assembly need not be a full-height wall.

13 PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR PREFABRICATED, COLD-FORMED STEEL, LATERAL-FORCE- RESISTING VERTICAL ASSEMBLIES (AC322) Representative Systems: A floor or wall system shall be considered representative if it is constructed in such a way that the stiffness and strength are similar to that which is expected to be encountered in typical usage. The use of less than full-height stud systems under the second floor platforms, and the use of floors constructed with reduced length members, is acceptable. Qualifying the prefabricated assembly performance for all floor framing alternatives is not necessarily required. Secondary connections required to transfer shear and overturning through the floor system shall also be constructed with materials and methods typical for the end use. The representative floor/wall systems, as well as the materials and methods for shear and overturning continuity, shall be fully detailed in the test report. The ICC-ES evaluation report shall specify these details or other equivalent details Initial Pretension of Overturning Restraint: The initial pretension of overturning restraint shall be as specified in Section of AC436, except that if wood perpendicular-to-grain stress is involved in transferring axial loads or overturning forces produced by the wall to the foundation, then the overturning restraint device (including anchor bolts) pretension shall not exceed 500 pounds (2,225 N). If the initial pretension is not monitored during the test, anchor bolt nuts shall be installed finger tight plus one-eighth turn Specimen Construction: The specimen construction shall be in accordance with Section of AC436, except that in the testing conducted on shear walls or other assemblies that rely on a structural plate for lateral resistance, the plate shall not bear on the top or bottom fixtures of the test frame Anchor Bolts: The strength and stiffness of the anchor bolts shall be representative of the anchor bolts used in the actual field construction Shrinkage Effects: For LFR elements installed on wood framing, the effects of wood shrinkage on LFR performance shall be addressed by calculations In-plane Cyclic Shear Testing with Superimposed Vertical Loads: If required by Section of this criteria, supplemental in-plane cyclic lateral shear testing with superimposed vertical loads shall be conducted in accordance with AC436, Section Exclusions of AC436 Sections: Section of AC436 is not applicable to AC322, since this section of AC436 addresses LFRVAs of Alternative Light-frame Construction, which are outside the scope of this criteria Section of AC436 is not applicable to AC322, since Section of this criteria includes evaluation provisions for panels intended for installations other than one-story supported on rigid foundations. 4.4 Data Analysis: General: Test data analysis shall be in accordance with AC436, Sections 3.1, 3.2, 3.3.1, through and Annex A, except with modifications noted in the following: Exclusions of AC436 Provisions: Provisions in AC436 Annex A Sections A1.2.1 and A2, regarding assemblies assigned with ASD strengths prescribed by the code, and which are intended to be a direct substitution of a code-prescribed light-frame shear wall assembly, are excluded from this criteria Provisions in AC436, Section are excluded from this criteria, since the requirements for engineering analysis and supplemental in-plane lateral shear testing are noted in Section of this criteria, above Data Extrapolation and Interpolation: Extrapolation of test results is not acceptable. Interpolation of test results is permitted provided all of the following conditions are satisfied: (1) The untested wall assembly consists of identical material as the tested assemblies; (2) The aspect (height/length) ratio of the untested assembly falls between the aspect ratios of the known tests being used for interpolation; (3) Interpolation is performed using the shape of a best fit curve as defined from the data points of at least three series of tests at differing aspect ratios; and (4) As required by Section of AC436, the controlling failure modes of the test assemblies used for interpolation are consistent among each other Strength and Drift Capacities of Replicate Specimens: For each LFRVA configuration with replicate specimens conforming to AC436, Section 4.1.8, Option (1), (2) or (3), the strength and drift values of the LFRVA configuration to be reported in the evaluation report are the average strength and drift, respectively, of the replicate specimens For each LFRVA configuration with replicate specimens conforming to AC436, Section 4.1.8, Option (4), the strength value of the LFRVA configuration to be reported in the evaluation report shall be the lowest strength value of the replicate specimens, and the corresponding drift value of the LFRVA configuration to be reported in the evaluation report shall be the average value of the replicate specimens Allowable Stress Design (ASD) (Seismic): Individual Specimen Load and Drift: The seismic ASD load capacity of each test assembly shall be derived in accordance with Section of this criteria, except that in lieu of Section A3.4.1 of AC436, the least value of PASD-Δ (based on a drift limit, per Section A3.2 of AC436), PASD-S (based on a strength limit, per Section A3.3 of AC436), and a calculation limit (or ASD seismic inplane shear strength determined in accordance with Section 4.2 of this criteria), shall be defined as PASD for the test specimen. In lieu of the requirements of Sections A3.2.5 and A3.3.2 of AC436, the drift corresponding to PASD, or ΔASD, for the test specimen shall be derived from the average envelope curve of the test specimen as defined in Section A1.3 of AC436. The PASD and ΔASD may be reduced in accordance with Section A3.1 of AC Seismic Equivalency Parameters: The individual load and drift values (or seismic equivalency parameters noted in AC436) for each test assembly determined under Section of this criteria and Section A3.4.2 of AC436, or the average values of the Page 4 of 6

14 PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR PREFABRICATED, COLD-FORMED STEEL, LATERAL-FORCE- RESISTING VERTICAL ASSEMBLIES (AC322) replicate specimens as directed in Section of AC436, shall be analyzed in accordance with Section of AC436 to establish seismic equivalency of the LFRVA Allowable Stress Design (Wind): The wind ASD load capacity of each test assembly shall be the least of the load capacities for the tested assembly based on a drift limit per Section , a strength limit per Section , and a calculation limit (or ASD wind in-plane shear strength determined in accordance with Section 4.2). The drift corresponding to this ASD load capacity shall be derived for each test assembly from the average envelope curve of the test assembly, as defined in Section A1.3 of AC436. The wind ASD load and drift capacities of the LFRVA configuration to be reported in the evaluation report shall be determined in accordance with Section of this criteria Drift Limit (Wind): The ASD load shall be equal to the load derived from the average envelope curve of each test specimen, noted in AC436, Annex A, Section A1.3 (also known as first-cycle backbone curve), at a deflection of H /180, where H is equal to the height of the tested assembly Strength Limit (Wind): The ASD load based on the strength of each test assembly shall be derived by dividing the peak test load, by a factor of safety of 2.0 for wind resistance Load and Resistance Factor Design (LRFD) Strength for Seismic and Wind: The LRFD strengths, of each LFRVA configuration for seismic load resistance and wind load resistance to be reported in the evaluation report, shall not exceed its corresponding ASD strengths determined in accordance with this criteria, multiplied by a factor of 1/0.7. For each test assembly, the seismic and wind LRFD drifts, corresponding to the seismic and wind LRFD load capacities of each LFRVA configuration, respectively, shall be derived from the average envelope curve of each test assembly. The seismic and wind LRFD drifts of the LFRVA configuration to be reported in the evaluation report shall be determined in accordance with Section of this criteria Additional CSRA Design Information: Where a prefabricated assembly is defined as a CSRA, information necessary for design shall be established that shall define the level and nature of the demand imposed on the attached structural elements (such as a header) due to lateral loading of the prefabricated assembly. The minimum stiffness of these elements shall correspond to the tested specimens. 4.5 Requirements for Non-DEDMs: For each non- DEDM portion of the SFRS, considering all applicable limit states, available strength established by testing or per AISI S400-15/S1-16, shall be greater than or equal to corresponding required strength per Section of this criteria Required Strength: The required strength of all structural members and connections in the lateralforce-resisting system that are not DEDMs, shall be determined per Sections B3.4 and E of AIS S400-15/S1-16, using the expected strength of the SFRS, but need not exceed the seismic load effect including overstrength. Accordingly, the required calculated strength Page 5 of 6 for Non-DEDMs shall be taken as the lesser of the following: 1. Ru = ΩoVn = 2.5 Ωo PASD, 2. Maximum demand from load combinations that include seismic demands multiplied by the overstrength factor, Ωo. 5.0 EVALUATING SEISMIC EQUIVALENCY TO CODE-PRESCRIBED LIGHT-FRAME SHEAR WALLS In order to be recognized as seismically equivalent to code-prescribed light frame shear walls sheathed with wood structural panels, and having seismic design parameters and limitations described in Table 1 of AC436, data for each LFRVA configuration shall be analyzed in accordance with Sections and of this criteria and Section of AC436, and shall satisfy the requirements in Sections and and Table 2 of AC QUALITY CONTROL 6.1 The product shall be manufactured under an approved quality control program with inspections by ICC- ES or by a properly accredited inspection agency that has a contractual relationship with ICC-ES. 6.2 A quality documentation system complying with the ICC-ES Acceptance Criteria for Quality Documentation (AC10) shall be submitted. 7.0 EVALUATION REPORT RECOGNITION The evaluation report shall include the following information: 7.1 Product information as required in Section 3.0 shall be included in the evaluation report. 7.2 The assembly identification label shall include the manufacturer s name and address, the evaluation report number, and other information deemed necessary by ICC- ES. The label shall be visible after the wall is installed. 7.3 For each LFRVA configuration, the strength and drift capacities determined in accordance with this criteria, shall be noted in the evaluation report. 7.4 Calculations and details, justifying that the use of the products qualified under this criteria is in compliance with the applicable code and the evaluation report, must be submitted to the code official for approval, except for those products, as identified in the evaluation report which are substitutions of braced walls and alternate braced walls. The calculations and details must be prepared by a registered design professional where required by the statutes of the jurisdiction in which the project is to be constructed. 7.5 Products qualified under this criteria are permitted to have the same seismic coefficients and factors and structural system limitations including height limits as those of Item A.15 of Table of ASCE/SEI 7-16 under the 2018 IBC, Item A.15 of Table of ASCE/SEI 7-10 under the 2015 and 2012 IBC (Item A.13 of Table of ASCE/SEI-05 under the 2009 and 2006 IBC). When the assemblies are installed in jurisdictions governed by the IBC, periodic inspections in Seismic Category C, D, E, or F shall be provided for the fastening and anchoring of the assembly within the seismic-forceresisting system including fastening of collectors (drag

15 PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR PREFABRICATED, COLD-FORMED STEEL, LATERAL-FORCE- RESISTING VERTICAL ASSEMBLIES (AC322) struts) and hold-downs, in accordance with the 2018 IBC Sections , , 2015 IBC Sections , and ; 2012 IBC Sections , and ; 2009 IBC Sections , and ; or 2006 IBC Sections and ; as applicable, unless exempted by applicable code and the exemption is approved by the code official. In jurisdictions governed by the IRC, special inspections are not required, except where an engineered design according to Section R of the IRC is used. Where an engineered design is used, special inspections in accordance with Section 7.5 must be provided. 7.6 Where recognition is sought for stacked multi-story applications, allowable design values, wall anchorage and detailing requirements, shall address the effects of cumulative overturning. 7.7 In addition to the requirements noted in this criteria, anchorage to concrete details (engineered design and details), in accordance with 2018 IBC Sections and 1905, 2015 IBC Sections and 1905; 2012 IBC Section 1909; or 2009 and 2006 IBC Section 1912, whichever is applicable, shall be submitted to ICC-ES. The engineered details will be included in the evaluation report. 7.8 The allowable loads in the evaluation report shall not include a 1.33 increase intended for multiple transient loading. The lateral shear-resisting assemblies qualified under this acceptance criteria are typically subjected to only one transient load at a time (seismic or wind). 7.9 When the seismic coefficients and factors assigned to the tested assemblies qualified under this criteria differ from those of other lateral-force-resisting assemblies installed in the same structure, structural design and construction must comply with IBC Section and ASCE/SEI 7 Sections through If the assembly is defined as a CSRA based upon Section 1.4.2, information identified in Section shall be included in the evaluation report If the assembly is defined as a CSRA based upon Section of this criteria, and a connection is made to a solid sawn lumber header (not an engineered wood product), documentation shall be provided to the building official verifying that the moisture content of the sawn lumber header is less than 19 percent at the time of installation The evaluation report shall clearly indicate that the product application is limited to use within light-framed wood or cold-formed steel construction complying with the code. TABLE 1 APPLICABLE EDITIONS OF REFERENCED STANDARDS REFERENCED STANDARD STANDARD EDITION 2018 IBC 2015 IBC 2012 IBC 2009 IBC 2006 IBC AISI S with Supplement No N/A AISI S200 N/A N/A AISI S N/A N/A N/A N/A AISI S with Supplement N/A N/A N/A N/A AISI NAS N/A N/A N/A N/A 2001 with 2004 supplement ASCE/SEI with Supplement No ASTM E or or or Including Supplements No. 1 and No. 2, excluding Chapter 14 and Appendix 11A. 2 Including Supplement No. 1, excluding Chapter 14 and Appendix 11A. Page 6 of 6