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:i:U N I RAC Unirac Code-Compliant Installation Manual SolarMount <br />Step 7: Determine adjustmentfactorfor height and <br />exposure category, A <br />Using the Exposure Category (Step 6) and the roof height, <br />h (ft)'lookup the adjustmentfactorfor height and exposure in <br />Table 4. <br />Table 4. Adjustment Factor (A) for Roof Height & <br />Exposure Category <br />Exposure <br />Mean roof <br />height (0 . 8 C · D <br />15 1.00 1.21 1.47 <br />20 1.00 1.29 1.55Step 8: Determine the Importance Factor, I <br />25 1.00 1.35 1.61 <br />Determine if the installation is in a hurricane prone region. 30 1.00 1.40 1.66 <br />Look up the Importance Facton 4 Table 6, bage 9, using the 35 I.05 1.45 1.70 <br />occupancy category description and the hurricane prone 40 1.09 1.49 1.74 <br />region status. 45 1.12 1.53 1.78 <br />50 1.16 1.56 1.81 <br />55 1.19 1.59 1.84 <br />Step 9: Calculate the Design Wind Load, pnet (psf) 60 1,22 1.62 1.87 <br />Multiply the Net Design Wind Pressure, pnet,0 (psf) (Step 4) by <br />Source: ASCEISEI 7-05, Minimum Design Loads for Buildings and Otherthe adjustment factor for height and exposure, X (Step 7),the Structures, Chapter 6, Figure 6-3, p. 44.Topographic Factor, Kzt (Step 5), and the Importance Factor, I <br />(Step 8) using the following equation, or Table 5 Worksheet. <br />Fnet (PSD = AKzd Fne£30 <br />pnet (psf) = Design Wind Load (10 psfminimum) <br />A = adjustmentfactorfor height and exposure category (Step 7) <br />Kzt = Topographic Factor at mean roof height, h (ft) (Step 53 <br />I = Importance Factor (Step 8) <br />pnet,0 (psf) = net design wind pressure for Exposure B, at height = <br />30, I=1 (Step 4) <br />Use Table 5 below to calculate Design Wind Load. <br />The Design Wind Load will be used in Part II to select the <br />appropriate SolarMount Series rail, rail span and foot spacing. <br />In Part II, use both the positive (downforce) and the negative · <br />(uplift) results from this calculation. <br />Table 5.Worksheet for Components and CladdingWind Load Calculation: IBC 2009,ASCE 7-05 <br />Variable Description <br />Ful@®glieight <br />Building, Least Horizontal Dimension <br />JRoof Pigh <br />Exposure Category <br />BEyVE¢_5@63 <br />Effective Wind Area <br />Symboj Value <br />h <br />Unit Step <br />ft · <br />ft ' <br />degreef <br />6 <br />mph : <br />sf <br />Reference <br />1 <br />1 <br />fjiGFECE] <br />2 <br />893! 76RisabTFICCEnith a tt 1 Table-I -7 <br />Roof Zone Location 3 Figure 2 <br />19*EPRiFi-Y'in-d_Pressure pneso pst 4 TAble-%32] <br />Topographic Factor Kzt x ' 5 <br />*Bjustmentiactor-for-Kzillund expgsfrg category-A x 7 Tabl©17-7 <br />Importance Factor I x 8 Table 5 <br />(Rijil [?Eiidwi63 -Load . pnet „ pd 9 - 1 <br />0 <br />Page <br />8