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• <br /> 3. The Makeup Air(MUA) fan for the main hood has a substantial weight <br /> (with air tempering (heating) feature) of about 500#. With all affected roof <br /> trusses having a shortened span with the support blocking, it may be <br /> installed without otherwise altering the roof structure and without further <br /> evaluation. <br /> 4. Important in the above unit evaluation is that they are each equally <br /> supported by two roof trusses (or close to it), per usual construction <br /> practice. Provided is a working sketch showing internal truss blocking and <br /> wood roof curbing recommended to ensure two trusses support each unit. <br /> 5. The two new hoods, 11-foot wide and 3-foot wide, are supported <br /> internally by new post supported 4" x 8" cross overhead beams. Beam <br /> posting is to the tenant space side wall and a new interior front to back <br /> wall. The interior wall may be OSB/plywood sheathed for general lateral <br /> post stability. <br /> 6. The beams are adequate by calculation for the larger hood and smaller <br /> hood. Calculations for beams attached. As noted, all beam ends will be <br /> posted in walls. Connecting hangers should be Simpson or equivalent for <br /> the 4"width beams ("high strength" not required, any standard 4" hanger <br /> is acceptable for this installation). Special post footing installation not <br /> required. The existing concrete slab is adequate for the relatively small <br /> post loading. <br /> 7. The roof-mounted installation of a minor bathroom fan and other minor <br /> installations in the rear portion of the tenant space is possible. Their <br /> installation is adequate by inspection, based on the wood beam structure <br /> in that area, by inspection. The front to back roof beam span in that area <br /> is only 20 feet. <br /> Summary. <br /> 1. Exhaust hood fans and MUA installation require added post and beam <br /> blocking from below under affected trusses to reduce the effective span of <br /> the 40-foot long front area roof trusses. (To be clear, the blocking of the <br /> trusses from below is the shorten the effective truss span, not to provide <br /> direct support for the new installed units.) <br /> 2. The new/replaced HVAC units will rest directly on the existing major <br /> cross beam. Their installation in that location has been evaluated and <br /> formal calculations of all loadings on the beam have been included. The <br /> existing glulam beam is adequate without additional support or alteration. <br />