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193866 - Cohen Rev A - LetterAugust 16, 2019 Valley Solar 340 Riverside Dr Northampton, MA 01062 RE Cohen Residence 44 Ward Ave, Northampton, MA 01060 Client Project #:44COHE PFE Project #: 193866 Revision: A - September 20, 2021 Updated Panel Quantity and Type On behalf of Valley Solar, Penn Fusion Engineering LLC (PFE) performed a structural analysis of the roof at the above referenced location. The purpose of our analysis was to determine if the existing roof system is structurally sufficient to support the new photovoltaic moudles in addition to the code required design loads. Our analysis is based on the information provided by Valley Solar and is limited only to the areas where the modules are intended to be placed. System Specifications Panel Specs: (20) Hanwha - Q Cells Racking System: Ecolibrium Solar - EcoFoot2+ The modules are to be located on the following roof planes: Roof Planes Mounting Plane Member Size Member Spacing Horizontal Span Sheathing Roofing Type Roofing Layers 1 2x10 16"13'-6"CDX 1/2"Asphalt Shingles 1 2 2x12 16"9'-0"CDX 1/2"Asphalt Shingles 1 Design Criteria Building Code(s)Ground Snow Pg Wind Speed V • 2015 International Residential Code (IRC) • ASCE 7-10 • Massachusetts State Building Code, Ninth Edition 40 psf 117 mph Analysis Results Mounting Plane Attachment Hardware Max Attachment Spacing Pass/Fail This office has determined that the installation of the PV System as specified above will meet the structural requirements of the above referenced codes when installed in accordance with the manufacture's instructions. Penn Fusion Engineering LLC - 152 S. Broad St. - Lansdale, PA 19446 - 215-361-8040 1 1 Ballast 7psf Max N/A Pass 2 Ballast 7psf Max N/A Pass If you have any questions regarding this analysis, please feel free to contact us. Best Regards, Penn Fusion Engineering, LLC Andrew D. Leone, P.E. Principal Penn Fusion Engineering LLC - 152 S. Broad St. - Lansdale, PA 19446 - 215-361-8040 2 Andrew D. Leone September 20, 2021 Client Name: Valley Solar Client Project Number: 44COHE Project: Cohen Residence Address: 44 Ward Ave, Northampton, MA 01060 PFE Project Number: 193866 Description: Mounting Plane 1 Roof Construction 2x10 Rafters at 16" on Center Species: Doug-Fir Larch #2 A: 13.88 in2 Fb: 900 psi Ix: 98.93 in4 Fv: 180 psi Sx: 21.39 in3 E: 1600000 psi Rafter Span: 13'-6" Ceiling Attached to Rafters: No Design Criteria Ground Snow (Pg): 40 psf Design Wind Speed (V): 117 mph Live Load: 20 psf Dead Load: 10.81 psf Wind Calculations Directionality Factor (Kd): 0.85 Topographic Factor (Kzt): 1 Vel. Press. Exp. Coef. (Kz): 0.7 Importance Factor (I): 1 Velocity Pressure (qz): 20.85 psf Trib. Sq. Ft. on Component: 10.83 ft2 Comp. Roof Pressures: 9.48 psf / -53.19 psf Snow Load Calculations Exposure Factor (Ce): 1 Thermal Factor (Ct): 1 Importance Factor (I): 1 Flat Roof Snow Load (Pf Roof Slope Factor (Cs): 1 Sloped Snow Load (Ps Unbalanced Snow Load: 0 psf Member Calculations Bending Md: 1269.88 ft-lb fb: 712.39 ft-lb Load Duration Factor (Cd): 1.15 Stability Factor (CL): 1 ft-lb Wet Service Factor (CM): 1 Temperature Factor (CT): 1 Size Factor (CF): 1.1 Flat Use Factor (Cfu): 1 Incising Factor (CI): 1 Repetitive Member Factor (Cr): 1.15 Fb: 900 psi F'b: 1309.28 psi 712.39 psi <= 1309.28 psi ∴ OK Shear Vd: 376.26 lb fv: 40.68 ft-lb Load Duration Factor (Cd): 1.15 Wet Service Factor (CM): 1 Temperature Factor (CT): 1 Size Factor (CF): 1.1 Flat Use Factor (Cfu): 1 Incising Factor (CI): 1 Fv: 180 psi F'v: 207 psi 40.68 psi <= 207 psi ∴ OK Deflection Live Load Deflection (ΔL):0.18 in L/919 OK Total Load Deflection (ΔT):0.26 in L/616 OK Penn Fusion Engineering LLC - 152 S. Broad St. - Lansdale, PA 19446 - 215-361-8040 C-1 PV Modules: 10 psf ): 40 psf ): 40 psf Roof Slope: 0° September 20, 2021 Client Name: Valley Solar Client Project Number: 44COHE Project: Cohen Residence Address: 44 Ward Ave, Northampton, MA 01060 PFE Project Number: 193866 Description: Mounting Plane 2 Roof Construction 2x12 Rafters at 16" on Center Species: Doug-Fir Larch #2 A: 16.88 in2 Fb: 900 psi Ix: 177.98 in4 Fv: 180 psi Sx: 31.64 in3 E: 1600000 psi Rafter Span: 9'-0" Ceiling Attached to Rafters: No Design Criteria Ground Snow (Pg): 40 psf Design Wind Speed (V): 117 mph Live Load: 20 psf Dead Load: 11.2 psf PV Modules: 3 psf Wind Calculations Directionality Factor (Kd): 0.85 Topographic Factor (Kzt): 1 Vel. Press. Exp. Coef. (Kz): 0.7 Importance Factor (I): 1 Velocity Pressure (qz): 20.85 psf Trib. Sq. Ft. on Component: 10.83 ft2 Comp. Roof Pressures: 9.48 psf / -53.19 psf Snow Load Calculations Exposure Factor (Ce): 1 Thermal Factor (Ct): 1 Importance Factor (I): 1 Flat Roof Snow Load (Pf Roof Slope Factor (Cs): 1 Sloped Snow Load (Ps Unbalanced Snow Load: 0 psf Member Calculations Bending Md: 569.66 ft-lb fb: 216.05 ft-lb Load Duration Factor (Cd): 1.15 Stability Factor (CL): 1 ft-lb Wet Service Factor (CM): 1 Temperature Factor (CT): 1 Size Factor (CF): 1 Flat Use Factor (Cfu): 1 Incising Factor (CI): 1 Repetitive Member Factor (Cr): 1.15 Fb: 900 psi F'b: 1190.25 psi 216.05 psi <= 1190.25 psi ∴ OK Shear Vd: 253.18 lb fv: 22.51 ft-lb Load Duration Factor (Cd): 1.15 Wet Service Factor (CM): 1 Temperature Factor (CT): 1 Size Factor (CF): 1 Flat Use Factor (Cfu): 1 Incising Factor (CI): 1 Fv: 180 psi F'v: 207 psi 22.51 psi <= 207 psi ∴ OK Deflection Live Load Deflection (ΔL):0.02 in L/5580 OK Total Load Deflection (ΔT):0.03 in L/3703 OK Penn Fusion Engineering LLC - 152 S. Broad St. - Lansdale, PA 19446 - 215-361-8040 C-2 Roof Slope: 0° ): 40 psf ): 40 psf