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Stamped PE Calcs - Kowalczyk, StevenFreedom Forever LLC 43445 Business Park Dr Suite 110 Temecula, CA 92590 Attn.: To Whom It May Concern re job:Kowalczyk, Steven 14 Walnut St Northampton, MA 01060 Design Criteria: Code:2015 IBC w/ 780 CMR ASCE 7-10 Live Load:20 psf Ult Wind Speed:117 mph Exposure Cat:B Ground Snow:40 psf Min Roof Snow:35 Current Renewables Engineering Inc. Professional Engineer info@currentrenewableseng.com 6/9/2021 The following calculations are for the structural engineering design of the photovoltaic panels and are valid only for the structural info referenced in the stamped plan set. The verification of such info is the responsibility of others. After review, I certify that the roof structure has sufficient structural capacity for the applied PV loads. All mounting equipment shall be designed and installed per manufacturer's approved installation specifications. Exp: 6/30/2022 CIVIL NO. 56313 VAOSMS IA GHAHR Date :6/9/2021 Job Code: Kowalczyk, Steven 2 of 6 Roof Properties: Roof Type = Roof Pitch (deg) = Mean Roof Height (ft) = Attachment Trib Width (ft) = Attachment Spacing (ft) = Framing Type = Framing Size = Framing OC Spacing (in.) = Section Thickness, b (in.) = Section Depth, d (in.) = Section Modulus, Sx (in.^3) = Moment of Inertia, Ix (in.^4) = Framing Span (ft) = Deflection Limit D+L (in.) = Deflection Limit S or W (in.) = Attachments Pattern = Framing Upgrade = Sister Size = Wood Species = Wood Fb (psi) = Wood Fv (psi) = Wood E (psi) = CD (Wind) = CD (Snow) = CLS = CM = Ct = CL = Ci = CF = Cfu = Cr = F'b_wind (psi) = F'b_snow (psi) = F'v_wind (psi) = F'v_snow (psi) = M_allowable_wind (lb-ft) = M_allowable_snow (lb-ft) = V_allowable_wind (lbs) = V_allowable_snow (lbs) =854 948 1188 155 1319 1504 216 1.15 2093 1.3 1.00 1.00 1.0 1.6 1.15 135 1400000 SPF #1 875 Adequate NA 1.40 Fully Staggered 10.5 2.1 7.6 20.8 1.5 5.5 2x6 24 4 Rafter 23 3.3 Shingle 33 Roof 1 Date :6/9/2021 Job Code: Kowalczyk, Steven 3 of 6 E' (psi) = Load Calculation: Panels Dead Load (psf) = Roofing Weight (psf) = Decking Weight (psf) = Framing Weight (psf) = Misc. Additional Weight (psf) = Existing Dead Load (psf) = Total Dead Load (psf) = Ground Snow Load, pg (psf) = Min Flat Snow, pf_min (psf) = Min Sloped Snow, ps_min (psf) = Snow Importance Factor, Ic = Exposure Factor, Ce = Thermal Factor, Ct = Flat Roof Snow, pf (psf) = Slope Factore, Cs = Sloped Roof Snow, ps (psf) = Ultimate Wind Speed (mph) = Directionality Factor, kd = Topographic Factor, kzt = Velocity Press Exp Factor, kz = Velocity Pressure, qz (psf) = External Pressure Up, GCp_1 = External Pressure Up, GCp_2 = External Pressure Up, GCp_3 = External Pressure Down, GCp = Design Pressure Up, p_1 (psf) = Design Pressure Up, p_2 (psf) = Design Pressure Up, p_3 (psf) = Design Pressure Down, p (psf) =17.7 -24.0 -24.0 0.85 -19.8 -1.15 -1.15 -0.95 0.70 20.9 117 0.85 1.0 Roof 1 24 Wind Load Calculations: 35 0.67 Roof 1 1.2 Snow Load Calculations: 40 35 NA 1.0 0.9 6.9 9.9 0.9 1.0 3.0 2.0 Dead Load Calculations: 3.0 Roof 1 1400000 Date :6/9/2021 Job Code: Kowalczyk, Steven 4 of 6 Hardware Checks: Ref. Widthrawal Value, W (lb/in) = (CM = Ct = Ceg = 1.0) CD = Adjusted Widthrawal Value, W' (lb/in) = Lag Penetration, p (in.) = Allowable Widthrawal Force, W'p (lbs) = Applied Uplift Force (lbs) = Uplift DCR = Ref. Lateral Value, Z (lbs) = (CM = Ct = CΔ = Ceg = 1.0) CD = Adjusted Lateral Value, Z' (lbs) = Applied Laeral Force (lbs) = Angle of Resultant Force, α (deg) = Adjusted Interaction Lateral Value, Z'α (lbs) = Lateral DCR = Roof Framing Checks: LC1: D+S Applied Moment (lb-ft) = Applied Shear (lbs) = Allowable Moment (lb-ft) = Allowable Shear (lbs) = Moment DCR = Shear DCR = LC2: D+0.6W Applied Moment (lb-ft) = Applied Shear (lbs) = Allowable Moment (lb-ft) = Allowable Shear (lbs) = Moment DCR = Shear DCR = LC3: D+0.75(S+0.6W) Applied Moment (lb-ft) = Applied Shear (lbs) = 980 373 0.43 0.18 1319 1188 567 216 0.97 0.41 948 854 351 Force Checks: Roof 1 922 369 0.52 191 36 1.15 288 0.17 250 820 -137 328 2.5 205 1.6 Lag Screw Checks: Roof 1 Date :6/9/2021 Job Code: Kowalczyk, Steven 5 of 6 Allowable Moment (lb-ft) = Allowable Shear (lbs) = Moment DCR = Shear DCR = LC4: 0.6D+0.6W Applied Moment (lb-ft) = Applied Shear (lbs) = Allowable Moment (lb-ft) = Allowable Shear (lbs) = Moment DCR = Shear DCR = LC1: D+L Deflection (in.) = Deflection Limit (in.) = Deflection DCR = LC2: S Deflection (in.) = Deflection Limit (in.) = Deflection DCR = LC3: W (Down) Deflection (in.) = Deflection Limit (in.) = Deflection DCR = LC4: W (Up) Deflection (in.) = Deflection Limit (in.) = Deflection DCR = Seismic Check: Wall Weight (psf) = Tributary Wall Area (ft2) = Total Wall Weight (lbs) = Roof Weight (psf) = Roof Area (ft2) = Total Roof Weight (lbs) = Total Existing Weight (lbs) = 1770 30090 7 814 5653 35743 0.11 Existing Weight: 17 -0.16 1.40 1.40 0.10 0.32 0.14 0.44 1.40 2.1 0.13 Deflection Checks (Service Level): Roof 1 0.28 0.12 0.05 1319 1188 163 62 0.74 0.31 1319 1188 Date :6/9/2021 Job Code: Kowalczyk, Steven 6 of 6 PV Panel Weight (lbs) = Number of Panels = Total Additional PV Weight (lbs) = (Existing W + Additional W)/(Existing W) =102% The increase in weight as a result of the solar system is less than 10% of the existing structure and therefore no further seismic analysis is required. Limits of Scope of Work and Liability: Existing structure is assumed to have been designed and constructed following appropriate codes at time of erection, and assumed to have appropriate permits. The calculations produced are only for the roof framing supporting the proposed PV installation referenced in the stamped planset and were completed according to generally recognized structural analysis standards and procedures, professional engineering and design experience, opinions and judgements. Existing deficiencies which are unknown or were not observable during time of inspection are not included in this scope of work. All PV modules, racking, and mounting equipment shall be designed and installed per manufacturer's approved installation specifications. The Engineer of Record and the engineering consulting firm assume no responsibility for misuse or improper installation. This analysis is not stamped for water leakage. Framing was determined based on information in provided plans and/or photos, along with engineering judgement. Prior to commencement of work, the contractor shall verify the framing sizes, spacings, and spans noted in the stamped plans, calculations, and cert letter (where applicable) and notify the Engineer of Record of any discrepancies prior to starting construction. Contractor shall also verify that there is no damaged framing that was not addressed in stamped plans, calculations, and cert letter (where applicable) and notify the Engineer of Record of any concerns prior to starting construction. Additional PV Weight: 54 15 817 Weight Increase: