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Wind Loads Calculations <br />Wind Design Parameters: <br />Ultimate Wind Speed, (Vult) = 110 mph Local Requirement <br />Risk Category = II <br />Wind Directionality Factor, Kd = 0.85 Table 26.6‐1 <br />Exposure Category = C <br />Topographic Factor, Kzt = 1.00 Table 26.8‐1 <br />Ground Elevation = 0 ft <br />Ground Elevation Factor, Ke = 1.00 Table 26.9‐1 <br />Mean Roof Height, h = 20 ft <br />Velocity Pressure Exposure Coefficient, Kz = 0.90 Table 26.10‐1 <br />Roof Slope = 16 degrees <br />Roof Type = Gable <br />Array Edge Factor, e = 1 Section 29.4.4 <br />Effective Wind Area = Standoff Tributary area (see below) <br />Calculations: <br />Velocity Pressure, qh (Ult)=0.00256∙Kz∙Kzt∙Ke∙V2 Eq. 26.10‐1 <br />Velocity Pressure, qh (Ult)=0.00256∙Kz∙Kzt∙Kd∙Ke∙V2 Eq. 26.10‐1 <br />= 27.96 psf <br />Design Wind Pressures, (Ult) =qh∙GCp∙Kd∙e∙a Eq.29.4‐7 <br />Design Wind Pressures, (Ult) =qh∙GCp∙e∙a Eq.29.4‐7 <br />Downward <br />Panel Orientation Both <br />Zone 1 (Interior) 2 (Edge) 3 (Corner) 1 (Interior) 2 (Edge) 3 (Corner) All  <br />Standoff spacing x‐ direction (in) 72.0 72.0 48.0 72.0 72.0 48.0 72.0 <br />Standoff spacing y‐ direction (in) 37.0 37.0 37.0 20.6 20.6 20.6 37.0 <br />Effective/Trib Wind Area (ft2)18.50 18.50 12.33 10.28 10.28 6.85 18.50 <br />Pressure Equalization Factor, a 0.71 0.71 0.77 0.80 0.80 0.80 0.71 <br />External Pressure Coefficient, GCp ‐1.73 ‐2.35 ‐3.44 ‐1.99 ‐2.68 ‐3.60 0.60 <br />Design Wind Pressure (Ult) (psf)‐29.18 ‐39.68 ‐62.83 ‐37.61 ‐50.79 ‐68.45 16.00 <br />Design Wind Pressure (ASD) (psf)‐17.51 ‐23.81 ‐37.70 ‐22.57 ‐30.47 ‐41.07 10.00 <br />Dead Load on Attachment (lbs) 55.5 55.5 37.0 30.8 30.8 20.6 55.5 <br />Attachment Net Uplift Forces (ASD) (lbs)‐291 ‐407 ‐443 ‐213 ‐295 ‐269 218 <br />*See Attachment Capacity Calculations for Demand/Capacity Ratio <br />Portrait Landscape <br />Uplift  <br />The wind loads on the standoffs and their attachment to the underlying structure are determined per the requirements for  <br />rooftop solar panels parallel to the roof surface (ASCE 7‐22, Section 29.4.4). <br />(Roof 1) 2 ‐ 5/16" dia. lag <br />P.O. Box 560, Broomfield, CO 80038 | projects@domusstruc.com | Page 4 of 8