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SRC Letter - Powers, Myles (1)DATE: 09-29-2020/Rev E FOR: Freedom Forever JOB: Powers, Myles 43445 Business Park Dr 92590 #110 218 Drury Lane Northampton, MA 01027 Temecula, CA 92590 USA To Whom It May Concern This letter is to certify that we have performed a structural analysis of the existing roof members that are to support photovoltaic panels, as shown on the attached report. The calculations were performed in accordance with the latest editions of IBC, NDS, ASCE/SEI, CBC, and IRC, and the 9th edition 2015 Massachusetts building code. Our analysis was based on the following design criteria: Ground Snow (psf) 40 psf Sloped Snow (psf), reduced per ASCE, Sect. 7.4 37.09 psf Basic Wind Speed (mph): 115 mph Roof Slope: 22 degrees The PV module orientation: Landscape The maximum horizontal roof mount spacing:4 ft. The maximum vertical roof mount spacing: 3.25 ft. Staggered roof mounts required? Yes Based on this analysis, we can certify that the individual existing roof framing members that support the PV panels; and the individual roof members as described in the attached report; are adequate to support the design loads as required by the various codes. This includes Dead Loads (including the weight of the PV panels), Live Loads, Snow Loads, and Wind Loads, on the roof members that support the PV panels, combined as required in the codes. If you have any questions on this or need further clarification, please contact us at your convenience. Sincerely, James A. Adams, S.E. NOTE: 1. Prior to commencement of work, the Solar Installer shall verify that the roof framing sizes, spacing, and spans (between supports), are as noted in these plans. The Engineer of Record must be notified if any discrepancies are discovered, before proceeding. 2. These plans are Stamped for Structural Code compliance of the roof members that support the PV solar system only. 3. These plans are not stamped for rain water leakage prevention. 4. As a precaution, old or wet snow should be removed from the roof, if the snow builds up to 18" or more. Digitally Signed by James A. Adams, S.E. Date: 2020.09.30 08:50:23 -0700 Date of Report: 09-29-2020/Rev E Job Name: Powers, Myles Data Input by: Kevin Nguyen Job Number: F060986 Contact E-mail: kevin@yoursolarplans.com Job Address: 218 Drury Lane Contact Phone: 7148721728 Northampton, MA 01027 ABSTRACT This Report is based on Engineering calculations using the input data supplied by the user, listed under Current Input Data. The user input has not been independently reviewed by a licensed Professional Engineer for appropriateness or accuracy, unless Stamped by a P.E. This Report indicates Compliance/Non-Compliance with the reference Codes listed below. The following items have been checked for Code Compliance: - Load Combination #1: Wind Uplift on the Standoff attachment to the Roof Framing members: Wind Uplift - 0.6 * DL Solar - Load Combination #2: Supporting Rafter Strength with: DL Rf + DL Solar + Roof Live Load - Load Combination #3: Supporting Rafter Strength with: DL Rf + DL Solar + Wind Down - Load Combination #4: Supporting Rafter Strength with: DL Rf + DL Solar + Snow - Load Combination #5: Supporting Rafter Strength with: DL Rf + DL Solar + .75Wind + .75Snow - Load Combination #6: Check Additional Seismic Load - Load Combination #7: Supporting Rafter Strength with: Wind Up - 0.6 * (DL Rf + DL Solar) Job Information Data Input By:Kevin Nguyen Job Number: F060986 Job Name: Powers, Myles Job Address: 218 Drury Lane City, State: Easthampton, MA 01027 Current Input Data Payment Method Invoice Roof Type SingleSpanRafters Ceiling Type 1/2 gyp. Bd. Collar Tie Space 0 Coverage % 41.4 Frame Size 2-2x6@24 Ground Snow (psf) 40 Sloped Roof Snow Load (psf) 37.09 Lag Screw Diam. (in) 5/16 Lag Screw Embed. (in) 2.5 Overall Span (ft) 27.5 PV Weight (psf) 2.5 PV Module Orientation Landscape Rafter Span (ft) 12 Rail System RailLess Roof Mean Height (ft) 25 Roof Slope (degrees) 22 Roofing Type Comp. Shingle Sloped Ceiling No Max. Horizontal Roof Mount(ft) 4 Max. Vertical Roof Mounts (ft) 3.25 Standoff Staggered Yes Wind Exposure C Wind Speed (mph) 115