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HomeMy WebLinkAboutLA205746 - APPROVED - Carey A Grant PE Calcs wStamp 08 23 2022Date: 08/23/2022 Job Number: 9580 Prepared for : Wolf River Electric, 101 Isanti Parkway NE, Isanti, MN 55040 Project.: Carey A Grant , 16003 Estate Ln, Lakeville, MN, v 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 PV mounting equipment shall be designed and installed per manufacturer's approved installation specifications. Engineerinc.io 303 N Glenoaks Blvd Suite 200 Burbank, CA 91502 (747) 333 - 5991 new@engineerinc.io Date Certified and Signed: 08/23/2022 303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io Solar Module Details Module Type HANWHA Module Quantity 49 Module Model Number 400 WATT Design Criteria Code: 2020 Minnesota Building Code (2018 IBC) ASCE 7-16 Live Load (psf)20 Ult Wind Speed (mph)125 Exposure Cat C Ground Snow (psf)50 Structure Geometry Eave Height, he (ft)15 to 20ft Pitch of main roof (deg)20 Building Length, L (ft)60 Building Width, B (ft)50 Roof Area (Module Area) ft2 3000.00 Standoff(i.e., Roof Mount) Spacing Feet 4` NOTE: attachments should be installed in a staggered configuratiion to properly destributor loading. Roof Properties Roof Geometry type Gable Roof Roof Type Truss Roof Pitch (deg)20 303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io Roofing Type Comp Shingles Sheathing Type 1/2" OSB Board Wood species No. 2, Douglas Fir-Larch Wood Fb (psf)900 Wood Fv (psf)180 Wood E (psf)1600000 Purlin C/C Spacing (in)12 Rafter C/C. Spacing (in.)24 Purlin Section Thickness, b (in.)2 Section Depth, d (in.)4 Rafter Section Thickness, b (in.)2 Section Depth, d (in.)4 Maximum Rafter Span (ft)7 Factors Cd(wind)1.60 Cd(Snow)1.60 CLS 1.15 CM 1 Ct 1 CL 0.75 CF 1.5 Cfu 1 Cv 1 Cr 1 M allowable_wind 413.44 M allowable_snow 297.16 303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io Dead Load(psf) Comp Shingles 3.00 psf 1/2" OSB Board 2.00 psf Insulation 2.00 psf Total Roof 1DL 7 psf No. 2, Douglas Fir-Larch 31.00 lb/ft3 Solar Panel DL 3.00 psf Roof 1 Roof_Dist_DL 7.00 psf M_Roof_Dist_DL 2493.86 Def_Roof_Dist_DL 1.48 PV_uni_Dist_DL 3.00 psf M_PV_uni_Dist_DL 10.54 Def_PV_uni_Dist_DL 0.01 Total_Uni_DL 11.00 psf M_Total_DL 2504.40 Def_Total_DL 1.49 Snow Load(psf) Ground Snow Load, pg 50 Importance Factor, Ic 1 Thermal Factor, Ct 1 Exposure Factor, Ce 1 Flat roof snow, pF 50 Slope Factor, Cs 1 303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io Sloped Row Snow, ps 50 Uni_Dist_S 50.00 M_uni_Dist_s 306.25 Def_uni_Dist_S 0.18 Wind Load Ultimate Wind Speed 125 Directionality Factor,kd 0.85 Topographic factor 1.00 Velocity pressure exposure factor,kz 0.88 Ground Elevation Factor,ke 2.16 Side Wall Width 50 Median Roof Height 129.36 Velocity pressure,qz 29.92 External Pressure Up,GCp_1 -0.7 External Pressure Up,GCp_2 -0.6 External Pressure Up,GCp_3 -1.3 External Pressure Down,GCp -0.18 Design Pressure Up,p_1 -17.51 Design Pressure Up,p_2 -15.01 Design Pressure Up,p_3 -32.52 Design Pressure Up,p -4.50 Uni_Dist_W_up -32.52 M_uni_Dist_W_up -199.19 Def_uni_Dist_W_up -0.12 Uni_Dist_W_down -4.50 303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io M_uni_Dist_W_down -27.56 Def_uni_Dist_W_down -0.02 Lag Screw Uplift Check (ASD) 5/16" Lag Screw Withdrawl value 205.00 lb/in Lag Screw Penetration 2.50 in Roof1 0.6D+0.6W(up z1)1699.566 > 512.5 Roof1 0.6D+0.6W(up z2)1701.066 > 512.5 Framing Check (ASD): Roof1 uni 1.0D+0.6W 2504.40 > 413.44 Lag Screw Penetration 2734.09 > 413.44 Roof1 0.6D+0.6W(up z1)2810.65 > 297.16 Roof1 0.6D+0.6W(up z2)1383.13 > 413.44 Seismic Check: Wood 5.00 psf 2x4 Studs @ 16"2.00 psf Gypsum 3.00 psf Misc(insulatioon,etc)2.00 psf Total wall DL 12.00 psf Total Wall Area (Approx)2590.00 ft2 Total Wall W 31080 lbs Total Roof DL 7.50 psf Total Roof Area (Approx)1276.93 ft2 Total Roof W 9576.975 lbs 303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io OK PV Panel W 3.00 psf Area of panel 980.00 ft2 Total Roof W 1381.77 lbs % increase=(Wadditional)/Wexisting 3.63% The increase in weight as a result of the solar system is less than 10% of the existing structure and therefore no furtherseismic 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 Engineerinc 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. Prior to the commencement of work, the contractor shall verify the existing roof and framing conditions. Notify Engineerinc and the engineer of record of any Discrepancies prior to starting construction. Prior to the commencement of work, the contractor shall inspect framing for any damage such as water damage, cracked framing, etc. and notify the E.O.R. if any issues are found.These plans/calculations are stamped for structural code compliance of the roof framing supporting the proposed PV installation reference only. These plans/calculations are not stamped for water leakage. PV modules, racking, and attachment components must follow manufacturer guidelines and requirements. 303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io