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ivin�• r_ j 1800 W Ashton Blvd. <br /> ! Lehi, UT 84043 <br /> Structural Group <br /> J. Matthew Walsh, PE Kirk M. Nelson, SE Samuel Brown, PE- Civil <br /> Director of Engineering Structural Engineering Structural Engineering <br /> james.walsh@vivintsolar.com kirk.nelson@vivintsolar.com sam.brown@vivintsolar.com <br /> October 11, 2019 <br /> Revised October 14,2019 <br /> Re: Structural Engineering Services <br /> Arango Residence <br /> 6720 Wagon Trail St,Zephyrhills, FL <br /> S-6230282; FL-01 <br /> To Whom It May Concern: <br /> We have reviewed the following information regarding solar panel installation on the roof of the above referenced <br /> home: <br /> 1. Site Visit by a representative from our office under my supervision identifying specific interior and <br /> exterior site information including the condition of the existing roof system and the size, spacing, and <br /> condition of existing structural framing members. Information gathered during the site visit includes <br /> photographs, sketches,and verification forms. <br /> 2. Design drawings of the proposed PV System layout, including details to mount the new solar panels to <br /> the existing roof. <br /> Based on the above information,we have evaluated the structural capacity of the existing roof system to support the <br /> additional loads imposed by the solar panels and have the following comments related to our review and evaluation: <br /> A. Description of Residence: <br /> The existing residence has typical wood framing construction with a maximum of two layers of composite shingle <br /> roofing. All wood material utilized for the roof system is assumed to be Southern Pine#2 or better with standard <br /> construction components. The designed areas of the home consist of the following framing methods: <br /> • Roof Sections: Prefabricated trusses at 24" on center. Survey photos indicate that there was free <br /> access to verify the framing size and spacing. <br /> B. Loading Criteria <br /> 8.02 PSF= Dead Load (roofing/framing) . <br /> 2.59 PSF= Dead Load (solar panels/mounting hardware) <br /> 10.61 PSF=Total Dead Load <br /> 20 PSF= Roof Live Load (based on local requirements) <br /> Wind speed of 145 mph (based on Exposure Category D-the total area subject to wind uplift is calculated for the <br /> Interior, Edge, and Corner Zones of the dwelling.) <br /> C. Required Structural Repairs <br /> The analysis performed has indicated that the existing roof will require the following repairs prior to installation of the <br /> photovoltaic array: <br /> Hip Framing-The mounting hardware is not designed to support the array with the roof framing running horizontally <br /> (cross-slope). At locations where mounting hardware will be installed, install 2x4 blocks between existing framing <br /> members. Each end of the blocks must be secured to the existing framing members with a Simpson Joist Hanger, <br /> Simpson A34 Clip Angle on each side(2 total), or with (2) 16d sinker nails into the end-grain of the block. <br /> Page 1 of 2 v' ® 'nt• .3 <br />