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410 <br /> NEW HEWITT/HODGES ASSOCIATES, LLC "as e 4 )/ <br /> HODGES BUILDING—ELEVATOR HOISTWAY ALTERATION January 12, 201 <br /> Review of Fire-Resistive.Construction Provisions <br /> part of this project. The removed column is indicated to be replaced with a new post located <br /> within the plane of the wall. <br /> CONSIDERATION <br /> The relative hazard of the vertical single-car hoistway is unchanged with this project. <br /> Therefore, it is reasonable to consider the new construction to be such that the existing <br /> building will be no less compliant with the provisions of the code than it was prior to the <br /> work; consistent with the language of IBC Section 3404.1 for alterations, presented above. <br /> In the presence of an automatic sprinkler system installed in accordance with IBC Section <br /> 903.3.1.1 throughout the existing Hodges Building,we understand City of Everett has <br /> identified that 1-hour FRR construction of the new elevator hoistway walls is acceptable, <br /> consistent with IBC Section 104.11; equivalent to the level of safety prescribed by fFC <br /> Section 1103.4.3 for existing hoistway walls. <br /> The new posts are identified to be of laminated strand lumber(LSL) material with a <br /> minimum nominal dimension of 4 inches, similar to provisions of IBC Section 602.4.5 for <br /> laminated construction in a heavy-timber bearing wall.As the remainder of the new wall is <br /> of 1-hour FRR light-weight construction, gwb protection should be installed on each side of <br /> the post within the wall cavity as well. <br /> The walls of the elevator hoistway are surrounded by the stair and do not adjoin a <br /> residential dwelling unit.Therefore, no particular sound (STC) rating is required by IBC <br /> Section 1207.1 for the elevator hoistway walls. <br /> The enlarged portion of the hoistway should be enclosed at the top in accordance with IBC <br /> Section 713.12.In addition,venting should be provided as prescribed by IBC Section <br /> 3004.2 at the top of the hoistway. <br /> CONCLUSION <br /> Consistent with the degree of fire-resistive construction prescribed by IFC Section 1103.4.3 <br /> for existing hoistway walls, and the level of safety recognized by City of Everett to be <br /> present consistent with IBC Section 104.11 in the presence of automatic fire sprinkler <br /> protection installed throughout the building in accordance with IBC Section 903.3.1.1, the <br /> new elevator hoistway wall assemblies should be minimum 1-hour FRR construction. <br /> Gypsum Association Fire Resistance Design Manual(GA-600)contains numerous generic <br /> 1-hour FRR wall assemblies for consideration, such as GA File No. WP 3510, WP 3514, <br /> WP 3520 and WP 3605. <br /> In accordance with IBC Section 713.12, the top of the enlarged portion of the hoistway <br /> should be enclosed or construction of the shaft should be extended to the underside of the <br /> roof. In addition, hoistway venting should be provided as prescribed by IBC Section 3004.2. <br /> AEGIS Engineering, PLLC <br />