Code-Complint Instlltion Mnul 809 Tble of Contents i. Letter of Certifiction..................................................................... 2 ii. Instller s Responsibilities................................................................ 3 Prt I. Procedure to Determine the Totl Design Wind Lod...................................... 4 Prt II. Procedure to Select Ril Spn nd Ril Type............................................. 11 Prt III. Instlling............................................................... 14 Pub 090828-1cc August 2009 Unirc welcomes input concerning the ccurcy nd user-friendliness of this publiction. Plese write to publictions@unirc.com. 2009 by Unirc, Inc. All rights reserved.
i. Instller s Responsibilities Plese review this mnul thoroughly before instlling your system. This mnul provides (1) supporting documenttion for building permit pplictions relting to Unirc s Universl PV Module Mounting system, nd (2) plnning nd ssembly instructions for products, when instlled in ccordnce with this bulletin, will be structurlly dequte nd will meet the structurl requirements of the IBC 2006, IBC 2003, ASCE 7-02, ASCE 7-05 nd Cliforni Building Code 2007 (collectively referred to s the Code ). Unirc lso provides limited wrrnty on products (pge 24). offers finish choices nd low, clen lines tht become s nturl prt of home s skylight. It delivers the instlltion ese you ve come to expect from Unirc. Whether for pitched roofs nd prking roof structures, ws designed from the outset to promote superior esthetics. Modules re flush mounted in low, gp-free rows, nd visible components mtch cler or drk module frmes. The instller is solely responsible for: Complying with ll pplicble locl or ntionl building codes, including ny tht my supersede this mnul; Ensuring tht Unirc nd other products re pproprite for the prticulr instlltion nd the instlltion environment; Ensuring tht the roof, its rfters, connections, nd other structurl support members cn support the rry under ll code level loding conditions (this totl building ssembly is referred to s the building structure); Using only Unirc prts nd instller-supplied prts s specified by Unirc (substitution of prts my void the wrrnty nd invlidte the letters of certifiction in ll Unirc publictions); Ensuring tht lg screws hve dequte pullout strength nd sher cpcities s instlled; Verifying the strength of ny lternte mounting used in lieu of the lg screws; Mintining the wterproof integrity of the roof, including selection of pproprite flshing; Ensuring sfe instlltion of ll electricl spects of the PV rry; nd Ensuring correct nd pproprite design prmeters re used in determining the design loding used for design of the specific instlltion. Prmeters, such s snow loding, wind speed, exposure nd topogrphic fctor should be confirmed with the locl building officil or licensed professionl engineer. 2
Prt I. Procedure to Determine the Design Wind Lod [1.1.] Using the Simplified Method - ASCE 7-05 The procedure to determine Design Wind Lod is specified by the Americn Society of Civil Engineers nd referenced in the Interntionl Building Code 2006. For purposes of this document, the vlues, equtions nd procedures used in this document reference ASCE 7-05, Minimum Design Lods for Buildings nd Other Structures. Plese refer to ASCE 7-05 if you hve ny questions bout the definitions or procedures presented in this mnul. Unirc uses Method 1, the Simplified Method, for clculting the Design Wind Lod for pressures on components nd cldding in this document. The method described in this document is vlid for flush, no tilt, Series pplictions on either roofs or wlls. Flush is defined s pnels prllel to the surfce (or with no more thn 3 difference between ends of ssembly) with no more thn 10 spce between the roof surfce, nd the bottom of the PV pnels. This method is not pproved for open structure clcultions. Applictions of these procedures is subject to the following ASCE 7-05 limittions: 1. The building height must be less thn 60 feet, h < 60. See note for determining h in the next section. For instlltions on structures greter thn 60 feet, contct your locl Unirc Distributor. 2. The building must be enclosed, not n open or prtilly enclosed structure, for exmple crport. 3. The building is regulr shped with no unusul geometricl irregulrity in sptil form, for exmple geodesic dome. 4. The building is not in n extreme geogrphic loction such s nrrow cnyon or steep cliff. 5. The building hs flt or gble roof with pitch less thn 45 degrees or hip roof with pitch less thn 27 degrees. 6. If your instlltion does not conform to these requirements plese contct your locl Unirc distributor, locl professionl engineer or Unirc If your instlltion is outside the United Sttes or does not meet ll of these limittions, consult locl professionl engineer or your locl building uthority. Consult ASCE 7-05 for more clrifiction on the use of Method I. Lower design wind lods my be obtined by pplying Method II from ASCE 7-05. Consult with licensed engineer if you wnt to use Method II procedures. The eqution for determining the Design Wind Lod for components nd cldding is: p net (psf) = Design Wind Lod p net (psf) = λk zt I p net30 λ = djustment fctor for height nd exposure ctegory K zt = Topogrphic Fctor t men roof height, h (ft) I = Importnce Fctor p net30 (psf) = net design wind pressure for Exposure B, t height = 30, I = 1 You will lso need to know the following informtion: Bsic Wind Speed = V (mph), the lrgest 3 second gust of wind in the lst 50 yers. h (ft) = totl roof height for flt roof buildings or men roof height for pitched roof buildings Effective Wind Are (sf) = minimum totl continuous re of modules being instlled Roof Zone = the re of the roof you re instlling the pv system ccording to Figure 2, pge 5. Roof Zone Setbck Length = (ft) Roof Pitch (degrees) Exposure Ctegory [1.2.] Procedure to Clculte Totl Design Wind The procedure for determining the Design Wind Lod cn be broken into steps tht include looking up severl vlues in different tbles. Step 1: Determine Bsic Wind Speed, V (mph) Determine the Bsic Wind Speed, V (mph) by consulting your locl building deprtment or locting your instlltion on the mps in Figure 1, pge 4. Step 2: Determining Effective Wind Are Determine the smllest re of continuous modules you will be instlling. This is the smllest re tributry (contributing lod) to support or to simple-spn of ril. Tht re is the Effective Wind Are. 3
Miles per hour (meters per second) Figure 1. Bsic Wind Speeds. Adpted nd pplicble to ASCE 7-05. Vlues re nominl design 3-second gust wind speeds t 33 feet bove ground for Exposure Ctegory C. Step 3: Determine Roof/Wll Zone The Design Wind Lod will vry bsed on where the instlltion is locted on roof. Arrys my be locted in more thn one roof zone. Using Tble 1, determine the Roof Zone Setbck Length, (ft), ccording to the width nd height of the building on which you re instlling the pv system. Tble 1. Determine Roof/Wll Zone, length () ccording to building width nd height = 10 percent of the lest horizontl dimension or 0.4h, whichever is smller, but not less thn either 4% of the lest horizontl dimension or 3 ft of the building. Roof Lest Horizontl Dimension (ft) Height (ft) 10 15 20 25 30 40 50 60 70 80 90 100 125 150 175 200 300 400 500 10 3 3 3 3 3 4 4 4 4 4 4 4 5 6 7 8 12 16 20 15 3 3 3 3 3 4 5 6 6 6 6 6 6 6 7 8 12 16 20 20 3 3 3 3 3 4 5 6 7 8 8 8 8 8 8 8 12 16 20 25 3 3 3 3 3 4 5 6 7 8 9 10 10 10 10 10 12 16 20 30 3 3 3 3 3 4 5 6 7 8 9 10 12 12 12 12 12 16 20 35 3 3 3 3 3 4 5 6 7 8 9 10 12.5 14 14 14 14 16 20 40 3 3 3 3 3 4 5 6 7 8 9 10 12.5 15 16 16 16 16 20 45 3 3 3 3 3 4 5 6 7 8 9 10 12.5 15 17.5 18 18 18 20 50 3 3 3 3 3 4 5 6 7 8 9 10 12.5 15 17.5 20 20 20 20 60 3 3 3 3 3 4 5 6 7 8 9 10 12.5 15 17.5 20 24 24 24 Source: ASCE/SEI 7-05, Minimum Design Lods for Buildings nd Other Structures, Chpter 6, Figure 6-3, p. 41. 4
Step 3: Determine Roof Zone (continued) Using Roof Zone Setbck Length,, determine the roof zone loctions ccording to your roof type, gble, hip or monoslope. Determine in which roof zone your pv system is locted, Zone 1, 2, or 3 ccording to Figure 2. Figure 2. Enclosed buildings, wll nd roofs Flt Roof Hip Roof (7 < θ 27 ) h h TYP Gble Roof ( θ 7 ) Gble Roof (7 < θ 45 ) h h Interior Zones Roofs - Zone 1/Wlls - Zone 4 End Zones Roofs - Zone 2/Wlls - Zone 5 Corner Zones Roofs - Zone 3 Source: ASCE/SEI 7-05, Minimum Design Lods for Buildings nd Other Structures, Chpter 6, p. 41. Step 4: Determine Net Design Wind Pressure, p net30 (psf) Using the Effective Wind Are (Step 2), Roof Zone Loction (Step 3), nd Bsic Wind Speed (Step 1), look up the pproprite Net Design Wind Pressure in Tble 2, pge 6. Use the Effective Wind Are vlue in the tble which is smller thn the vlue clculted in Step 2. If the instlltion is locted on roof overhng, use Tble 3, pge 7. Both downforce nd uplift pressures must be considered in overll design. Refer to Section II, Step 1 for pplying downforce nd uplift pressures. Positive vlues re cting towrd the surfce. Negtive vlues re cting wy from the surfce. 5
Tble 2. p net30 (psf) Roof nd Wll Zone Effective Wind Are (sf) Bsic Wind Speed, V (mph) 90 100 110 120 130 140 150 170 Downforce Uplift Downforce Uplift Downforce Uplift Downforce Uplift Downforce Uplift Downforce Uplift Downforce Uplift Downforce Uplift Roof 0 to 7 degrees Roof 7 to 27degrees Roof 27 to 45 degrees 1 10 5.9-14.6 7.3-18.0 8.9-21.8 10.5-25.9 12.4-30.4 14.3-35.3 16.5-40.5 21.1-52.0 1 20 5.6-14.2 6.9-17.5 8.3-21.2 9.9-25.2 11.6-29.6 13.4-34.4 15.4-39.4 19.8-50.7 1 50 5.1-13.7 6.3-16.9 7.6-20.5 9.0-24.4 10.6-28.6 12.3-33.2 14.1-38.1 18.1-48.9 1 100 4.7-13.3 5.8-16.5 7.0-19.9 8.3-23.7 9.8-27.8 11.4-32.3 13.0-37.0 16.7-47.6 2 10 5.9-24.4 7.3-30.2 8.9-36.5 10.5-43.5 12.4-51.0 14.3-59.2 16.5-67.9 21.1-87.2 2 20 5.6-21.8 6.9-27.0 8.3-32.6 9.9-38.8 11.6-45.6 13.4-52.9 15.4-60.7 19.8-78.0 2 50 5.1-18.4 6.3-22.7 7.6-27.5 9.0-32.7 10.6-38.4 12.3-44.5 14.1-51.1 18.1-65.7 2 100 4.7-15.8 5.8-19.5 7.0-23.6 8.3-28.1 9.8-33.0 11.4-38.2 13.0-43.9 16.7-56.4 3 10 5.9-36.8 7.3-45.4 8.9-55.0 10.5-65.4 12.4-76.8 14.3-89.0 16.5-102.2 21.1-131.3 3 20 5.6-30.5 6.9-37.6 8.3-45.5 9.9-54.2 11.6-63.6 13.4-73.8 15.4-84.7 19.8-108.7 3 50 5.1-22.1 6.3-27.3 7.6-33.1 9.0-39.3 10.6-46.2 12.3-53.5 14.1-61.5 18.1-78.9 3 100 4.7-15.8 5.8-19.5 7.0-23.6 8.3-28.1 9.8-33.0 11.4-38.2 13.0-43.9 16.7-56.4 1 10 8.4-13.3 10.4-16.5 12.5-19.9 14.9-23.7 17.5-27.8 20.3-32.3 23.3-37.0 30.0-47.6 1 20 7.7-13.0 9.4-16.0 11.4-19.4 13.6-23.0 16.0-27.0 18.5-31.4 21.3-36.0 27.3-46.3 1 50 6.7-12.5 8.2-15.4 10.0-18.6 11.9-22.2 13.9-26.0 16.1-30.2 18.5-34.6 23.8-44.5 1 100 5.9-12.1 7.3-14.9 8.9-18.1 10.5-21.5 12.4-25.2 14.3-29.3 16.5-33.6 21.1-43.2 2 10 8.4-23.2 10.4-28.7 12.5-34.7 14.9-41.3 17.5-48.4 20.3-56.2 23.3-64.5 30.0-82.8 2 20 7.7-21.4 9.4-26.4 11.4-31.9 13.6-38.0 16.0-44.6 18.5-51.7 21.3-59.3 27.3-76.2 2 50 6.7-18.9 8.2-23.3 10.0-28.2 11.9-33.6 13.9-39.4 16.1-45.7 18.5-52.5 23.8-67.4 2 100 5.9-17.0 7.3-21.0 8.9-25.5 10.5-30.3 12.4-35.6 14.3-41.2 16.5-47.3 21.1-60.8 3 10 8.4-34.3 10.4-42.4 12.5-51.3 14.9-61.0 17.5-71.6 20.3-83.1 23.3-95.4 30.0-122.5 3 20 7.7-32.1 9.4-39.6 11.4-47.9 13.6-57.1 16.0-67.0 18.5-77.7 21.3-89.2 27.3-114.5 3 50 6.7-29.1 8.2-36.0 10.0-43.5 11.9-51.8 13.9-60.8 16.1-70.5 18.5-81.0 23.8-104.0 3 100 5.9-26.9 7.3-33.2 8.9-40.2 10.5-47.9 12.4-56.2 14.3-65.1 16.5-74.8 21.1-96.0 1 10 13.3-14.6 16.5-18.0 19.9-21.8 23.7-25.9 27.8-30.4 32.3-35.3 37.0-40.5 47.6-52.0 1 20 13.0-13.8 16.0-17.1 19.4-20.7 23.0-24.6 27.0-28.9 31.4-33.5 36.0-38.4 46.3-49.3 1 50 12.5-12.8 15.4-15.9 18.6-19.2 22.2-22.8 26.0-26.8 30.2-31.1 34.6-35.7 44.5-45.8 1 100 12.1-12.1 14.9-14.9 18.1-18.1 21.5-21.5 25.2-25.2 29.3-29.3 33.6-33.6 43.2-43.2 2 10 13.3-17.0 16.5-21.0 19.9-25.5 23.7-30.3 27.8-35.6 32.3-41.2 37.0-47.3 47.6-60.8 2 20 13.0-16.3 16.0-20.1 19.4-24.3 23.0-29.0 27.0-34.0 31.4-39.4 36.0-45.3 46.3-58.1 2 50 12.5-15.3 15.4-18.9 18.6-22.9 22.2-27.2 26.0-32.0 30.2-37.1 34.6-42.5 44.5-54.6 2 100 12.1-14.6 14.9-18.0 18.1-21.8 21.5-25.9 25.2-30.4 29.3-35.3 33.6 40.5 43.2-52.0 3 10 13.3-17.0 16.5-21.0 19.9-25.5 23.7-30.3 27.8-35.6 32.3-41.2 37.0-47.3 47.6-60.8 3 20 13.0-16.3 16.0-20.1 19.4-24.3 23.0-29.0 27.0-34.0 31.4-39.4 36.0-45.3 46.3-58.1 3 50 12.5-15.3 15.4-18.9 18.6-22.9 22.2-27.2 26.0-32.0 30.2-37.1 34.6-42.5 44.5-54.6 3 100 12.1-14.6 14.9-18.0 18.1-21.8 21.5-25.9 25.2-30.4 29.3-35.3 33.6-40.5 43.2-52.0 Wll 6 4 10 14.6-15.8 18.0-19.5 21.8-23.6 25.9-28.1 30.4-33.0 35.3-38.2 40.5-43.9 52.0-56.4 4 20 13.9-15.1 17.2-18.7 20.8-22.6 24.7-26.9 29.0-31.6 33.7-36.7 38.7-42.1 49.6-54.1 4 50 13.0-14.3 16.1-17.6 19.5-21.3 23.2-25.4 27.2-29.8 31.6-34.6 36.2-39.7 46.6-51.0 4 100 12.4-13.6 15.3-16.8 18.5-20.4 22.0-24.2 25.9-28.4 30.0-33.0 34.4-37.8 44.2-48.6 4 500 10.9-12.1 13.4-14.9 16.2-18.1 19.3-21.5 22.7-25.2 26.3-29.3 30.2-33.6 38.8-43.2 5 10 14.6-19.5 18.0-24.1 21.8-29.1 25.9-34.7 30.4-40.7 35.3-47.2 40.5-54.2 52.0-69.6 5 20 13.9-18.2 17.2-22.5 20.8-27.2 24.7-32.4 29.0-38.0 33.7-44.0 38.7-50.5 49.6-64.9 5 50 13.0-16.5 16.1-20.3 19.5-24.6 23.2-29.3 27.2-34.3 31.6-39.8 36.2-45.7 46.6-58.7 5 100 12.4-15.1 15.3-18.7 18.5-22.6 22.0-26.9 25.9-31.6 30.0-36.7 34.4-42.1 44.2-54.1 5 500 10.9-12.1 13.4-14.9 16.2-18.1 19.3-21.5 22.7-25.2 26.3-29.3 30.2-33.6 38.8-43.2 Source: ASCE/SEI 7-05, Minimum Design Lods for Buildings nd Other Structures, Chpter 6, Figure 6-3, p. 42-43.
Tble 3. p net30 (psf) Roof Overhng Roof 27 to 45 degrees Roof 7 to 27degrees Roof 0 to 7 degrees Zone Effective Wind Are (sf) Bsic Wind Speed, V (mph) 90 100 110 120 130 140 150 170 2 10-21.0-25.9-31.4-37.3-43.8-50.8-58.3-74.9 2 20-20.6-25.5-30.8-36.7-43.0-49.9-57.3-73.6 2 50-20.1-24.9-30.1-35.8-42.0-48.7-55.9-71.8 2 100-19.8-24.4-29.5-35.1-41.2-47.8-54.9-70.5 3 10-34.6-42.7-51.6-61.5-72.1-83.7-96.0-123.4 3 20-27.1-33.5-40.5-48.3-56.6-65.7-75.4-96.8 3 50-17.3-21.4-25.9-30.8-36.1-41.9-48.1-61.8 3 100-10.0-12.2-14.8-17.6-20.6-23.9-27.4-35.2 2 10-27.2-33.5-40.6-48.3-56.7-65.7-75.5-96.9 2 20-27.2-33.5-40.6-48.3-56.7-65.7-75.5-96.9 2 50-27.2-33.5-40.6-48.3-56.7-65.7-75.5-96.9 2 100-27.2-33.5-40.6-48.3-56.7-65.7-75.5-96.9 3 10-45.7-56.4-68.3-81.2-95.3-110.6-126.9-163.0 3 20-41.2-50.9-61.6-73.3-86.0-99.8-114.5-147.1 3 50-35.3-43.6-52.8-62.8-73.7-85.5-98.1-126.1 3 100-30.9-38.1-46.1-54.9-64.4-74.7-85.8-110.1 2 10-24.7-30.5-36.9-43.9-51.5-59.8-68.6-88.1 2 20-24.0-29.6-35.8-42.6-50.0-58.0-66.5-85.5 2 50-23.0-28.4-34.3-40.8-47.9-55.6-63.8-82.0 2 100-22.2-27.4-33.2-39.5-46.4-53.8-61.7-79.3 3 10-24.7-30.5-36.9-43.9-51.5-59.8-68.6-88.1 3 20-24.0-29.6-35.8-42.6-50.0-58.0-66.5-85.5 3 50-23.0-28.4-34.3-40.8-47.9-55.6-63.8-82.0 3 100-22.2-27.4-33.2-39.5-46.4-53.8-61.7-79.3 Source: ASCE/SEI 7-05, Minimum Design Lods for Buildings nd Other Structures, Chpter 6, p. 44. Step 5: Determine the Topogrphic Fctor, K zt For the purposes of this code complince document, the Topogrphic Fctor, K zt, is tken s equl to one (1), mening, the instlltion is on level ground (less thn 10% slope). If the instlltion is not on level ground, plese consult ASCE 7-05, Section 6.5.7 nd the locl building uthority to determine the Topogrphic Fctor. Step 6: Determine Exposure Ctegory (B, C, D) Determine the Exposure Ctegory by using the following definitions for Exposure Ctegories. exposure c hs open terrin with scttered obstructions hving heights generlly less thn 30 feet. This ctegory includes flt open country, grsslnds, nd ll wter surfces in hurricne prone regions. exposure d hs flt, unobstructed res nd wter surfces outside hurricne prone regions. This ctegory includes smooth mud flts, slt flts, nd unbroken ice. Also see ASCE 7-05 pges 287-291 for further explntion nd explntory photogrphs, nd confirm your selection with the locl building uthority. The ASCE/SEI 7-05* defines wind exposure ctegories s follows: exposure b is urbn nd suburbn res, wooded res, or other terrin with numerous closely spced obstructions hving the size of single fmily dwellings. 7
Step 7: Determine djustment fctor for height nd exposure ctegory, λ Using the Exposure Ctegory (Step 6) nd the roof height, h (ft), look up the djustment fctor for height nd exposure in Tble 4. Step 8: Determine the Importnce Fctor, I Determine if the instlltion is in hurricne prone region. Look up the Importnce Fctor, I, Tble 6, pge 9, using the occupncy ctegory description nd the hurricne prone region sttus. Step 9: Clculte the Design Wind Lod, p net (psf) Multiply the Net Design Wind Pressure, p net30 (psf)(step 4) by the djustment fctor for height nd exposure, λ (Step 7),the Topogrphic Fctor, K zt (Step 5), nd the Importnce Fctor, I (Step 8) using the following eqution: Tble 4. Adjustment Fctor (λ) for Roof Height & Exposure Ctegory Men roof height (ft) Exposure B C D 15 1.00 1.21 1.47 20 1.00 1.29 1.55 25 1.00 1.35 1.61 30 1.00 1.40 1.66 35 1.05 1.45 1.70 40 1.09 1.49 1.74 45 1.12 1.53 1.78 50 1.16 1.56 1.81 55 1.19 1.59 1.84 60 1.22 1.62 1.87 Source: ASCE/SEI 7-05, Minimum Design Lods for Buildings nd Other Structures, Chpter 6, Figure 6-3, p. 44. p net (psf) = λk zt I p net30 p net (psf) = Design Wind Lod (10 psf minimum) λ = djustment fctor for height nd exposure ctegory (Step 7) K zt = Topogrphic Fctor t men roof height, h (ft) (Step 5) I = Importnce Fctor (Step 8) p net30 (psf) = net design wind pressure for Exposure B, t height = 30, I = 1 (Step 4) Use Tble 5 below to clculte Design Wind Lod. The Design Wind Lod will be used in Prt II to select the pproprite Series ril, ril spn nd foot spcing. Tble 5. Worksheet for Components nd Cldding Wind Lod Clcultion: IBC 2006, ASCE 7-05 Vrible Description Symbol Vlue Unit Step Reference Building Height h ft Building, Lest Horizontl Dimension ft Roof Pitch degrees Exposure Ctegory 6 Bsic Wind Speed V mph 1 Figure 1 Effective Roof Are sf 2 Roof Zone Setbck Length ft 3 Tble 1 Roof Zone Loction 3 Figure 2 Net Design Wind Pressure p net30 psf 4 Tble 2, 3 Topogrphic Fctor K zt x 5 Adjustment fctor for height nd exposure ctegory λ x 7 Tble 4 Importnce Fctor I x 8 Tble 5 Totl Design Wind Lod p net psf 9 8
Tble 6. Occupncy Ctegory Importnce Fctor Ctegory Ctegory Desicription Building Type Exmples Non-Hurricne Prone Regions nd Hurricne Prone Regions with Bsic Wind Speed, V = 85-100 mph, nd Alsk Hurricne Prone Regions with Bsic Wind Speed, V > 100mph I Buildings nd other structures tht represent low hzrd to humn life in the event of filure, including, but limited to: Agriculturl fcilities Certin Temporry fcilities Minor Storge fcilities 0.87 0.77 II All buildings nd other structures except those listed in Occupncy Ctegories I, III, nd IV. 1 1 III Buildings nd other structures tht represent substntil hzrd to humn life in the event of filure, including, but not limited to: Buildings where more thn 300 people congregte Schools with cpcity more thn 250 Dy Cres with cpcity more thn 150 Buildings for colleges with cpcity more thn 500 Helth Cre fcilities with cpcity more thn 50 or more resident ptients Jils nd Detention Fcilities Power Generting Sttions Wter nd Sewge Tretment Fcilities Telecommuniction Centers Buildings tht mnufcture or house hzrdous mterils 1.15 1.15 IV Buildings nd other structures designted s essentil fcilities, including, but not limited to: Hospitls nd other helth cre fcilities hving surgery or emergency tretment Fire, rescue, mbulnce nd police sttions Designted erthquke, hurricne, or other emergency shelters Designted emergency prepredness communiction, nd opertion centers Power generting sttions nd other public utility fcilities required in n emergency Ancillry structures required for opertion of Occupncy Ctegory IV structures Avition control towers, ir trffi c control centers, nd emergency ircrft hngrs Wter storge fcilities nd pump structures required to mintin wter pressure for fi re suppression Buildings nd other structures hving criticl ntionl defense functions 1.15 1.15 Source: IBC 2006, Tble 1604.5, Occupncy Ctegory of Buildings nd other structures, p. 281; ASCE/SEI 7-05, Minimum Design Lods for Buildings nd Other Structures, Tble 6-1, p. 77 9
Prt II. Procedure to Select Ril Spn nd Ril Type [2.1.] Using Stndrd Bem Clcultions, Structurl Engineering Methodology The procedure to determine the Unirc series ril type nd ril spn uses stndrd bem clcultions nd structurl engineering methodology. The bem clcultions re bsed on simply supported bem conservtively, ignoring the reductions llowed for supports of continuous bems over multiple supports. Plese refer to Prt I for more informtion on bem clcultions, equtions nd ssumptions. In using this document, obtining correct results is dependent upon the following: 1. Obtin the Snow Lod for your re from your locl building officil. 2. Obtin the Design Wind Lod, p net. See Prt I (Procedure to Determine the Design Wind Lod) for more informtion on clculting the Design Wind Lod. 3. Plese Note: The terms ril spn nd footing spcing re interchngeble in this document. See Figure 3 for illustrtions. 4. To use Tble 8 nd Tble 9 the Ded Lod for your specific instlltion must be less thn 5 psf, including modules nd Unirc rcking systems. If the Ded Lod is greter thn 5 psf, see your Unirc distributor, locl structurl engineer or contct Unirc. The following procedure will guide you in selecting Unirc ril for flush mount instlltion. It will lso help determine the design loding imposed by the Unirc PV Mounting Assembly tht the building structure must be cpble of supporting. Step 1: Determine the Totl Design Lod The Totl Design Lod, P (psf) is determined using ASCE 7-05 2.4.1 (ASD Method equtions 3,5,6 nd 7) by dding the Snow Lod 1, S (psf), Design Wind Lod, p net (psf) from Prt I, Step 9 nd the Ded Lod (psf). Both Uplift nd Downforce Wind Lods clculted in Step 9 of Prt 2 must be investigted. Use Tble 7 to clculte the Totl Design Lod for the lod cses. Use the mximum bsolute vlue of the three downforce cses nd the uplift cse for sizing the ril. Use the uplift cse only for sizing lg bolts pull out cpcities (Prt II, Step 6). P (psf) = 1.0D + 1.0S 1 (downforce cse 1) P (psf) = 1.0D + 1.0p net (downforce cse 2) P (psf) = 1.0D + 0.75S 1 + 0.75p net (downforce cse 3) P (psf) = 0.6D + 1.0p net (uplift) D = Ded Lod (psf) S = Snow Lod (psf) p net = Design Wind Lod (psf) The mximum Ded Lod, D (psf), is 5 psf bsed on mrket reserch nd internl dt. 1 Snow Lod Reduction - The snow lod cn be reduced ccording to Chpter 7 of ASCE 7-05. The reduction is function of the roof slope, Exposure Fctor, Importnce Fctor nd Therml Fctor. Plese refer to Chpter 7 of ASCE 7-05 for more informtion. Figure 3. Ril spn nd footing spcing re interchngeble. Ril Spn or Foot Spcing L 10 Note: Modules must be centered symmetriclly on the rils (+/- 2*), s shown in Figure 3. If this is not the cse, cll Unirc for ssistnce. B Module length perpendiculr to rils
Tble 7. ASCE 7 ASD Lod Combintions Description Vrible Downforce Cse 1 Downforce Cse 2 Downforce Cse 3 Uplift units Ded Lod D 1.0 x 1.0 x 1.0 x 0.6 x psf Snow Lod S 1.0 x + 0.75 x + psf Design Wind Lod Pnet 1.0 x + 0.75 x + 1.0 x - psf Totl Design Lod P psf Note: Tble to be filled out or ttched for evlution. Step 2: Determine the Distributed Lod on the ril, w (plf) Determine the Distributed Lod, w (plf), by multiplying the module width, B (ft), by the Totl Design Lod, P (psf). Use the mximum bsolute vlue of the three downforce cses nd the Uplift Cse. We ssume ech module is supported by one ril. w = PB w = Distributed Lod (pounds per liner foot, plf) Using the distributed lod, w, from Prt II, Step 2, look up the llowble spns, L, for. There re two tbles, L-Foot Series Ril Spn Tble nd Double L-Foot Series Ril Spn Tble. The L-Foot Series Ril Spn Tble uses single L-foot connection to the roof, wll or stnd-off. The point lod connection from the ril to the L-foot cn be incresed by using double L-foot in the instlltion. Plese refer to Prt III for more instlltion informtion. B = Module Length Perpendiculr to Rils (ft) P = Totl Design Pressure (pounds per squre foot, psf) Step 3: Determine Ril Spn/ L-Foot Spcing Tble 8. L-Foot Series Ril Spn Spn (ft) w = Distributed Lod (plf) 20 25 30 40 50 60 80 100 120 140 160 180 200 220 240 260 280 300 400 500 600 700 2 SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF 2.5 SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF 3 SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF 3.5 SF SF SF SF SF SF SF SF SF SF SF SF SF SF 4 SF SF SF SF SF SF SF SF SF SF SF SF SF 4.5 SF SF SF SF SF SF SF SF SF SF SF 5 SF SF SF SF SF SF SF SF SF SF SF 5.5 SF SF SF SF SF SF SF SF SF SF 6 SF SF SF SF SF SF SF SF SF 6.5 SF SF SF SF SF SF SF SF SF 7 SF SF SF SF SF SF SF SF 7.5 SF SF SF SF SF SF SF SF 8 SF SF SF SF SF SF SF SF 8.5 SF SF SF SF SF SF SF 9 SF SF SF SF SF SF 9.5 SF SF SF SF SF SF 10 SF SF SF SF SF 10.5 SF SF SF SF 11 SF SF SF SF 11.5 SF SF SF 12 SF SF SF 12.5 SF SF 13 SF SF 13.5 SF 14 SF 11
Tble 9. Double L-Foot Series Ril Spn Spn (ft) w = Distributed Lod (plf) 20 25 30 40 50 60 80 100 120 140 160 180 200 220 240 260 280 300 400 500 600 700 2 SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF 2.5 SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF 3 SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF 3.5 SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF SF 4 SF SF SF SF SF SF SF SF SF SF SF SF SF SF 4.5 SF SF SF SF SF SF SF SF SF SF SF SF 5 SF SF SF SF SF SF SF SF SF SF 5.5 SF SF SF SF SF SF SF SF SF 6 SF SF SF SF SF SF SF SF 6.5 SF SF SF SF SF SF SF 7 SF SF SF SF SF SF 7.5 SF SF SF SF SF SF 8 SF SF SF SF SF 8.5 SF SF SF SF SF 9 SF SF SF SF 9.5 SF SF SF SF 10 SF SF SF 10.5 SF SF SF 11 SF SF SF 11.5 SF SF 12 SF SF 12.5 SF 13 SF 13.5 SF 14 Step 4: Select Ril Type Selecting spn ffects the price of your instlltion. Longer spns produce fewer wll or roof penetrtions. However, longer spns crete higher point lod forces on the building structure. A point lod force is the mount of force trnsferred to the building structure t ech connection. It is the instller s responsibility to verify tht the building structure is strong enough to support the point lod forces. Step 5: Determine the Downforce Point Lod, R (lbs), t ech connection bsed on ril spn When designing the Unirc Flush Mount Instlltion, you must consider the downforce Point Lod, R (lbs) on the roof structure. The Downforce, Point Lod, R (lbs), is determined by multiplying the Totl Design Lod, P (psf) (Step 1) by the Ril Spn, L (ft) (Step 3) nd the Module Length Perpendiculr to the Rils, B (ft). R (lbs) = PLB R = Point Lod (lbs) P = Totl Design Lod (psf) L = Ril Spn (ft) B = Module Length Perpendiculr to Rils (ft) It is the instller s responsibility to verify tht the building structure is strong enough to support the mximum point lods clculted ccording to Step 5. 12
Tble 10. Downforce Point Lod Clcultion Totl Design Lod (downforce) (mx of cse 1, 2 or 3) P psf Step 1 Module length perpendiculr to rils B x ft Ril Spn L x ft Step 4 Downforce Point Lod R lbs Step 6: Determine the Uplift Point Lod, R (lbs), t ech connection bsed on ril spn You must lso consider the Uplift Point Lod, R (lbs), to determine the required lg bolt ttchment to the roof (building) structure. Tble 11. Uplift Point Lod Clcultion Totl Design Lod (uplift) P psf Step 1 Module length perpendiculr to rils B x ft Ril Spn L x ft Step 4 Uplift Point Lod R lbs Tble 12. Lg pull-out (withdrwl) cpcities (lbs) in typicl roof lumber (ASD) Specifi c grvity Lg screw specifi ctions 5 16 shft,* per inch thred depth Dougls Fir, Lrch 0.50 266 Dougls Fir, South 0.46 235 Engelmnn Spruce, Lodgepole Pine (MSR 1650 f & higher) 0.46 235 Use Tble 12 to select lg bolt size nd embedment depth to stisfy your Uplift Point Lod Force, R (lbs), requirements. It is the instller s responsibility to verify tht the substructure nd ttchment method is strong enough to support the mximum point lods clculted ccording to Step 5 nd Step 6. Hem, Fir, Redwood (close grin) 0.43 212 Hem, Fir (North) 0.46 235 Southern Pine 0.55 307 Spruce, Pine, Fir 0.42 205 Thred depth Spruce, Pine, Fir (E of 2 million psi nd higher grdes of MSR nd MEL) 0.50 266 Sources: Americn Wood Council, NDS 2005, Tble 11.2A, 11.3.2A. Notes: (1) Thred must be embedded in the side grin of rfter or other structurl member integrl with the building structure. (2) Lg bolts must be locted in the middle third of the structurl member. (3) These vlues re not vlid for wet service. (4) This tble does not include sher cpcities. If necessry, contct locl engineer to specifi y lg bolt size with regrd to sher forces. (5) Instll lg bolts with hed nd wsher fl ush to surfce (no gp). Do not over-torque. (6) Withdrwl design vlues for lg screw connections shll be multiplied by pplicble djustment fctors if necessry. See Tble 10.3.1 in the Americn Wood Council NDS for Wood Construction. *Use fl t wshers with lg screws. 13
Prt III. Instlling The Unirc Code-Complint Instlltion Instructions supports pplictions for building permits for photovoltic rrys using Unirc PV module mounting systems. This mnul, Ril Plnning nd Assembly, governs instlltions using the systems. [3.1.] ril components 3 6 3 Figure 4. components. 2 7 8 1 9 2 1 5 1 12 4 5 1 4 9 8 10 11 Figure 5. threded slot ril, cross section, ctul size. 14
11. Ril Supports PV modules. Use one per row of modules plus one. Shipped in 8- or 16-foot lengths. 6105-T5 luminum extrusion, nodized (cler or drk bronze) to mtch PV module frme. 2. Cp strip Secures PV modules to rils nd netly frmes top of rry. Lengths equls ril lengths. Cp strips re sized for specific PV modules. Shipped in 8- or 16-foot lenghs. Predrilled every 8 inches. 6105-T5 luminum extrusion, nodized (cler or drk bronze) to mtch PV module frme. 3. Cp strip screw (¼-20 x 1, Type F thred cutting) Use to secure ech cp strip (nd PV modules) to ril, one per predrilled hole. Use n dditionl end screw wherever predrilled hole does not fll within 4 inches of the end of ny cp strip segment. 18-8 stinless steel, cler or blck to mtch cp strip. 4. Ril splice Joins ril sections into single length of ril. It cn form either rigid or therml expnsion joint. 8 inches long, predrilled. 6105-T5 luminum extrusion, nodized (cler or drk bronze) to mtch PV module frme. 5. Self-drilling screw (No. 10 x 3 /4 ") Use 4 per rigid splice or 2 per expnsion joint. Glvnized steel. 6. End cps Use one to netly close ech ril end. UV resistnt blck plstic. 77. Truss-hed sheet metl screw (No. 8 x 5 /8 ") Use 2 per end cp to secure end cp to ril. 18-8 stinless steel; with blck oxide coting to mtch end cps. 8. L-foot Use to secure rils either through roofing mteril to rfters, to L-foot djusting sliders, or to stndoffs. Use no less thn one L-foot per 4 feet of ril. 6105-T5 luminum extrusion, nodized (cler or drk bronze) to mtch PV module frme. 9. L-foot bolt ( 3 /8 " x 1 1 /4 ") Use one per L-foot to secure ril to L-foot. 304 stinless steel. 10. Flnge nut ( 3 /8 " ) Use one per L-foot bolt. 304 stinless steel. 11. L-foot djusting slider (optionl) Use one beneth ech L-foot or luminum two-piece stndoff, except in lowest row. 6105-T5 luminum extrusion. Sliders llow esier lignment of rils nd better snugging of PV modules between rils. Includes 3 /8 " x 1 1 /4 " bolt with flnge nut for ttching L-foot or stndoff shft, nd two 5 /16" x 2 1 /2" lg bolts with flt wshers for securing sliders to rfters. 12. Flttop stndoff (optionl) Use if L-foot cnnot be secured directly to rfter (with tile or shke roofs, for exmple). Use one per L-foot. Two-piece (pictured): 6105-T5 luminum extrusion. Includes 3 /8" x 3 /4" serrted flnge bolt with EPDM wsher for ttching L-foot, nd two 5 /16 " x 3 1 /2" lg bolts. One-piece: Service Condition 4 (very severe) zinc-plted welded steel. Includes 3 /8 " x 1 1 /4 " bolt with lock wsher for ttching L-foot. Flshings: Use one per stndoff. Unirc offers pproprite flshings for both stndoff types. Instller supplied mterils: Lg screw for L-foot Attches L-foot or stndoff to rfter. Determine length nd dimeter bsed on pull-out vlues in Tble 3 (pge 13). If lg screw hed is exposed to elements, use stinless steel. Under flshings, zinc plted hrdwre is dequte. Note: Lg screws re provided with L-foot djusting sliders nd stndoffs. Wterproof roofing selnt Use selnt pproprite to your roofing mteril. Clmps for stnding sem metl roof See Frequently Asked Questions... (p. 23). Stinless steel hrdwre cn seize up, process clled glling. To significntly reduce its likelihood, (1) pply lubricnt to bolts, preferbly n nti-seize lubricnt, vilble t uto prts stores, (2) shde hrdwre prior to instlltion, nd (3) void spinning on nuts t high speed. See Instlltion Supplement 910, Glling nd Its Prevention, t www.unirc.com. 15
Instlling the rry Sfe, efficient instlltion involves three principl tsks: A. Lying out the instlltion re nd plnning for mteril conservtion. B. Instlling footings nd rils, beginning with the lowest row nd moving up the roof. C. Plcing modules nd cp strips, beginning with the highest row nd moving down the roof. The following illustrted steps describe the procedure in detil. Before beginning, plese note these importnt considertions. Footings must be lgged into structurl members. Never ttch them to the decking lone, which leves both the rry nd roof susceptible to severe dmge. For rry widths or lengths greter thn 32 feet, contct Unirc concerning therml expnsion issues. Smple lyout, illustrted in Figure 6 Assumptions: 12 modules (60 x 36 ), rrnged in 3 rows of 4 modules Arry width = 144 (36 module width x 4 modules per row) Arry length = 180 (60 module length x 3 rows) + 3 (1½ end ril width x 2 rils) + 1½ (¾ between-module ril width x 2 rils) = 184½ 1½ t ech end of rry ¾ spce between module rows Roof pek 1. Lying out the instlltion re Alwys instll rils perpendiculr to rfters. (These instructions ssume typicl rfters tht run from the gutter to the pek of the roof. If this is not the cse, contct Unirc.) Rils re typiclly mounted horizontlly (prllel to the lower edge of the roof), nd must be mounted within 10 degrees of horizontl. Leve dequte room to move sfely round the rry during instlltion. During module instlltion, you will need to slide one module in ech row bout foot beyond the end of the rils on one side. Using the number of rows nd the number of modules per row in your instlltion, determine the size of your rry re following Figure 6. Arry length ¾ 1½ Module length (see cption) Module width Arry width (module width times modules per row) Rils Figure 6. Instlltion re lyout. Note: Module length is not necessrily mesured from the edges of the frme. Some frmes hve lips. Others re ssembled with pn-hed screws. All such fetures must be included in module length. 16
2. Instlling the lowest row of L-feet nd ril In the lowest row, it is not necessry to use L-foot djusting sliders, even if you pln to use them in subsequent rows. Instll L-feet directly onto low profile roofing mteril such s sphlt shingles or sheet metl. (For high profile roofs, such s tile or shke, use optionl stndoffs with flshing to rise L-feet. L-feet must be flush with or bove the highest point of the roof surfce.) L-feet cn be plced with the double-slotted side ginst the roof surfce (s in Fig. 7) or with the single-slotted side ginst the roof (which increses ir circultion beneth modules). Module-to-roof dimensions re listed on pge 19 for both rrngements. L feet If you re using L-foot djusting sliders, you must use the short side of the the L-foot ginst the roof in the first row. See Figure 9 below. If you re using both L-foot djusting sliders nd stndoffs, see the upper box on pge 18. Lg screw Alwys lg into slot nerest the bend in the L-foot Instll the first row of L-feet t the lower edge of the instlltion re (Fig. 8). Ensure feet re ligned by using chlk line. (A ril cn lso be used s stright edge.) Position the L-feet with respect to the lower edge of the roof s illustrted in Figures 7 nd 8. Figure 7. Plcement of first L-foot row. Drill pilot hole through roof into the center of the rfter t ech L-foot lg screw hole loction. Apply wetherproof selnt into the hole nd onto shfts of the lg screws. Sel the underside of the L-feet with suitble wetherproof selnt. Fsten the L-feet to the roof with the lg screws. If the double slotted sides of the L-feet re ginst the roof, lg through the slot nerest the bend in the L-foot (Figs. 7 nd 8). 2¾ Lower edge of instlltion re Roof pek Utility slot for No. 10 screw Utility slot for 1 / 4 hexhed bolt Slot for 3 / 8 footing bolt Roof pek Cut the rils to your rry width, being sure to keep ril slots free of roofing grit or other debris. If your instlltion requires splices, ssemble them prior to Figure 8. L-Foot orienttion. ttching L-feet (see Footing nd splicing requirements, p. 18, nd Mteril plnning for rils nd cp strips, p. 20). Slide the 3 / 8-inch mounting bolts into the footing slots. If more thn one splice is used on ril, slide L-foot bolt(s) into the footing slot(s) of the interior ril segment(s) before splicing. Loosely ttch the rils to the L-feet with the flnge nuts. Ensure tht rils re oriented with respect to the L-feet s shown in Figure 9. Align the ends of the ril to the edge of the instlltion re. Ensure tht the ril is stright nd prllel to the edge of the roof. Then tighten the lg screws. Figure 9. L-foot orienttion in conjunction with L-foot djusting sliders. The sliders include two utility slots to secure module wiring, combiner boxes, nd other system components. 17
Using stndoffs with L-foot djusting sliders Two-piece luminum stndoffs my be used with footing sliders, lthough flshings my not be vilble to cover the entire length of the slider. Use the bses of the stndoffs only in the lowest row. In subsequent rows, ttch the shft of ech stndoff to the slider using the slider s 3 /8-inch hexhed bolt. Note tht L-feet re positioned long side up on the lowest rows nd with long side down in subsequent rows in the sme mnner s n instlltion with no stndoffs. With stndoffs of equl length, orient L-foot to compenste for height difference. If the stndoff supporting the lowest ril is 1 inch tller thn the stndoffs on the footing sliders, plce both L-feet in the sme orienttion either both long side up or both short side up. B A L-foot This exmple ssumes ril seven times the length of the footing spcing (A). A splice my be locted in ny of the shded res. If more thn one splice is used, be sure the combintion does not violte Requirements 5, 6, or 7. Footing nd splicing requirements The following criteri re required for sound instlltions. While short sections of ril re structurlly permissible, they cn usully be voided by effective plnning, which lso promotes superior esthetics. See Mteril plnning for rils nd cp strips (p. 20). The instller is solely responsible for ensuring tht the roof nd its structurl members cn support the rry nd its live lods. For ril lengths exceeding 48 feet, therml expnsion joints my be necessry. Plese contct Unirc. 1. Footing spcing long the ril (A in illustrtion bove) is determined by wind loding (see pp. 2 3, especilly step 1). Foot spcing t 48 inches is dvised. 2. Overhng (B) must be no more thn hlf the length of the mximum footing spcing (A). For exmple, if Spn A is 32 inches, Overhng B should not exceed 16 inches. 3. Do not locte splice in the center third of the spn between two djcent feet. 4. In spliced length of ril, ll end sections must be supported by no less thn two L-feet. 5. All interior ril sections must be supported by no less thn one L-foot. 6. Interior ril sections supported by only one L-foot must be djcent, on t lest one side, to ril section supported by no less thn two L-feet. 7. Ril sections longer thn hlf the footing spcing require no fewer thn two L-feet. Rfters Stringer Ril Modules should lwys be fully supported by rils. In other words, modules should never overhng rils. This is especilly criticl when supporting the short side of non-rectngulr module. When ril supports pir of nonrectngulr modules by themselves (right), it must be supported by t lest two L-feet. The ril should be t lest 14 nd no more thn 24 inches long, which will likely require stringer between rfters to ensure proper footings. Non-rectngulr modules 18
3. Lying out nd instlling the next row of L-feet With L-feet only: Position the second row of L-feet in ccordnce with Figure 10. Ensure tht you mesure between the lower bolt hole centers of ech row of L-feet. Instll the second row of L-feet in the sme mnner nd orienttion s the first row, but leve the lg screws hlf turn loose. Be wre of the set-up time of your selnt; the L-feet will not be fully tightened until Step. 4. With L-foot djusting sliders: Use chlk line to mrk the position of the slider center holes of the next row. The illustrtion below provides spcing guidelines. The length of the module (A in Fig. 11) includes ny protrusions, such s lips or pn-hed screws in its frme. Attch nd sel L-foot djusting slider: Instll lower lg first, footing bolt next, nd upper lg lst. Attch n L-foot with its short side up to ech slider. Module length + ¾ (hole to hole) Figure 10. L-foot seprtion. See the note on module length in the cption of Figure 3 (p. 10). Roof pek A = module length A A Align slider center hole to chlk line Lowest row of L-feet (no footing sliders) A + 1 3 /16 A + 2 1 /4 A + 3 /4 A - 3 1 /4 Align slider center hole to chlk line Figure 11. If you re using L-foot djusting sliders, this spcing between rows plces L-feet t the center of their djustment rnge. 4. Instlling the second ril With L-feet only (Fig. 12): Instll nd lign the second ril in the sme mnner nd orienttion s the first ril. After ril lignment, tighten the ril mounting bolts. Ly one module in plce t one end of the rils, nd snug the upper ril (Fig. 12) towrd the lower ril, leving no gp between the ends of the modules nd either ril. (If pn-hed screw heds represent the true end of the modules, be sure the screw heds touch the rils on both ends.) Tighten the lg screw on tht end. Slide the module down the rils, snugging the rils nd tightening the remining lg screws s you go. With L-foot djusting sliders: Instll rils on first nd second rows of L-feet. Verify spcing by plcing module onto the rils t severl points long the row. Adjust L-foot positions s needed. Module Lg screw (tight) Figure 12. Position nd secure top ril. Snug Lg screw (hlf turn loose) 5. Instlling remining L-feet nd rils Instll the L-feet nd the rils for the remining rows, following Steps 3 nd 4. You my use the sme module to spce ll the rows. When complete, confirm tht: All rils re fitted nd ligned. All footing bolts nd lg screws re secure. The module used for fitting is resting (but not secured) in the highest row. 19
Mteril plnning for rils nd cp strips Preplnning mteril use for your prticulr rry cn prevent structurl or esthetic problems, prticulrly those cused by very short lengths of ril or cp strip. This exmple illustrtes one pproch. Structurl requirements for rils re detiled in Footing nd splicing requirements (p.18). Structurlly, cp strips require: A screw in every prepunched hole (which occur every 8 inches, beginning 4 inches from the ends of the rils). One screw 4 inches or less from the ech end of every ril segment. Wherever there is no prepunched hole within 4 inches of n end of segment, drill 1 / 4-inch hole 2 inches from the end of the segment nd instll cp strip screw. (In most cses, you cn void this sitution with good mteril plnning.) Structurl requirements lwys tke precedence, but usully good plnning cn lso chieve both mteril conservtion nd superior esthetics. This exmple conserves mteril nd chieves two specific esthetic gols: Cp strip screws must lign cross the rils. End screws must be equidistnt from both sides of the rry. The exmple ssumes n rry of three rows, ech holding five modules 41 inches wide. Thus, four 205-inch ril Arry center line ssemblies nd cp strip ssemblies need to be cut nd spliced from 192-inch sections of ril nd cp strip. The exmple illustrtes one mens of doing so, without violting structurl requirements or esthetic gols. Ril segments come from five 192-inch lengths, lettered A thru E. Ril A, for exmple, is cut into two 96-inch segments, with one segment spliced into ech of the first two rils. Similrly, five 192-inch cp strips re designted V through Z. All cp strip segments re cut t the midpoint between prepunched screw holes. For ech ril, strt with the cp strip segment tht crosses the rry center line, nd position over the center line so tht the pproprite holes re spced eqully on either side. Position ech cp strip onto its ril nd mrk its trim point. Remove nd trim before finl mounting. Preliminry footing nd splice positions must be checked ginst structurl requirements in Footing nd splicing requirements (p.18). In this exmple, the center of the rry is offset 2 inches from the center rfter. This prevents ril splices BD (3rd ril) nd CE (4th ril) from flling too close to the center of the spns between footings (Requirement 3, p. 18). Becuse footings re not visible from ground level, there is negligible esthetic loss. Trim line (rry edge) V 112 C 83 Trim line (rry edge) X 96 E 122 1st cp strip 4th ril W 112 B 83 X 96 D 122 2nd cp strip 3rd ril V 80 A 96 Y 128 C 109 3rd cp strip 2nd ril W 80 Z 128 A 96 B 109 4th cp strip 1st ril Usble reminder: D, 70 ; E, 70 ; Y, 64 ; Z, 64 20
6. Securing the first module Gther sufficient lengths of cp strip to cover the length of the first ril. For mximum visul ppel nd mteril conservtion see Mteril plnning for rils nd cp strips (p. 20). Slide the first module into finl position t one end of the rry. Ly the remining modules in the top row, leving gp bout foot wide between the first nd second modules (Fig. 13). The temporry gp llows the instller to plce one of his feet between modules. He cn ccess the section of the cp strip he needs to secure while lening towrd the pek of the roof. For the time being, the lst module my overhng the ril by up to one third its width. Attch the end of the cp strip with the cp strip screws (Fig. 13, inset), so tht the upper end of the first module is secure. Cp strip screws Stepping gp Figure 13. Begin cp strip instlltion. Permissble overhng: 1/3 module width Do not instll second cp strip until lower modules re plced The structurl integrity of your rry requires tht cp strip screws fully engge the threded ril. Use the cp strip screws supplied with your cp strips. Any substitute screws must be ¼-20 Type F thred cutting (18-8 stinless steel) nd the correct length. Every cp strip segment must hve cp strip screw 4 inches or less from ech end. If the nerest predrilled hole flls more thn 4 inches from ny end, drill ¼-inch hole 2 inches from the end nd instll n dditionl screw. Wherever it is necessry to mke new cp strip hole, drill ¼-inch hole before instlling the cp strip screw. 2. Instll screws 1. Slide Stepping gp Figure 14. Position nd secure modules one by one. 7. Instlling the remining modules in the top row Slide the next module into finl position nd instll the screws to secure it (Fig. 14). For net instlltion, use cble ties to ttch excess wiring to the ril beneth the flnges. Unirc s cble ties cn be ttched to the ril by drilling ¼-inch hole in the ril nd pushing the end of the tie into the hole. Continue the process until ll modules in the top row re in finl plce nd secured from the top. When complete, every prepunched hole in the cp strip will be secured by screw, nd the top end of the first row of modules will be secure. 8. Instlling the remining modules row by row Repet Steps 6 nd 7 for the remining rows (Fig. 15). Ech subsequent cp strip will secure the tops to the modules being instlled nd the bottoms of the modules in the row bove. Plce the finl cp strip in the lowest ril, securing the bottom of the lowest module row. Secured 1st module Slide nd secure one by one Stepping gp Figure 15. As modules slide into plce, the stepping gp shifts, lwys llowing ccess to the section of cp strip being secured. 21
9. Instlling the end cps Attch the end cps to the ends of the rils by securing with the truss hed sheet metl screws provided (Fig. 16). Figure 16. End cp instlltion. Tble 4: PV module, cp strip, nd cp strip screw comptibility To ensure code complince nd structurlly sound rry, cp strip sizes nd cp strip screw lengths must be comptible with the PV modules in your instlltion. All cp strip screws must be ¼-20 Type F thred cutting (18-8 stinless steel). Module thickness or type Cp strip Required screw inches mm cross section Cp strip size length (inches) 1.34 1.42 34 36 C ¾" 1.50 1.57 38 40 D ¾" 1.77 1.85 45 47 F 1¼" 1.93 2.01 49 51 E 1¼" Shrp lipped modules G 1" Snyo lipped modules H ¾" 22
Frequently sked questions bout stndoffs nd roof vritions How high bove the roof is rry? The nswer depends on the orienttion of your L-feet nd the length of your stndoffs, if used. See the illustrtion pproprite to your instlltion. How cn I sel the roof penetrtion required when stndoffs re lgged below the roofing mteril? Mny types nd brnds of flshing cn be used with Sun- Frme. Unirc offers n Otey No-Clk flshings for its steel stndoffs nd Otey or Unirc flshings for its luminum two-piece stndoffs. See our Pro-Pk Price List. How do I ttch to stnding-sem metl roof? A good solution comes from Metl Roof Innovtions, Ltd. (MRI). They mnufcture the S-5! clmp, designed to ttch wide vriety of products to most stnding-sem metl roofs. It is n elegnt solution tht elimintes flshings nd penetrtions ltogether. L-feet will mount to the top of the S-5! clmps with the 3 / 8-inch stinless steel bolt provided with the S-5! See www.s-5solutions.com for different clmp models nd detils regrding instlltion. When using S-5! clmps, mke sure tht there re enough clmp/l-feet ttchments to the metl roof to meet the Metl Roof Mnufcturers nd MRI specifictions regrding wind lods, etc. Module thickness vries Module thickness vries 2 1 / 4 ± 1 /8 7/8 ± 1/8 Module thickness vries 2 1 / 4 ± 1 /8 7/8 ± 1/8 3 1 / 8 ± 1 /8 1 3 / 4 ± 1 /8 Stndoff height (3, 4, 6, or 7 ll ± 1 / 8 ) 23
10 yer limited Product Wrrnty, 5 yer limited Finish Wrrnty Unirc, Inc., wrrnts to the originl purchser ( Purchser ) of product(s) tht it mnufctures ( Product ) t the originl instlltion site tht the Product shll be free from defects in mteril nd workmnship for period of ten (10) yers, except for the nodized fi nish, which fi nish shll be free from visible peeling, or crcking or chlking under norml tmospheric conditions for period of fi ve (5) yers, from the erlier of 1) the dte the instlltion of the Product is completed, or 2) 30 dys fter the purchse of the Product by the originl Purchser ( Finish Wrrnty ). The Finish Wrrnty does not pply to ny foreign residue deposited on the fi nish. All instlltions in corrosive tmospheric conditions re excluded. The Finish Wrrnty is VOID if the prctices specified by AAMA 609 & 610-02 Clening nd Mintennce for Architecturlly Finished Aluminum (www.mnet.org) re not followed by Purchser. This Wrrnty does not cover dmge to the Product tht occurs during its shipment, storge, or instlltion. This Wrrnty shll be VOID if instlltion of the Product is not performed in ccordnce with Unirc s written instlltion instructions, or if the Product hs been modified, repired, or reworked in mnner not previously uthorized by Unirc IN WRITING, or if the Product is instlled in n environment for which it ws not designed. Unirc shll not be lible for consequentil, contingent or incidentl dmges rising out of the use of the Product by Purchser under ny circumstnces. If within the specified Wrrnty periods the Product shll be resonbly proven to be defective, then Unirc shll repir or replce the defective Product, or ny prt thereof, in Unirc s sole discretion. Such repir or replcement shll completely stisfy nd dischrge ll of Unirc s libility with respect to this limited Wrrnty. Under no circumstnces shll Unirc be lible for specil, indirect or consequentil dmges rising out of or relted to use by Purchser of the Product. Mnufcturers of relted items, such s PV modules nd fl shings, my provide written wrrnties of their own. Unirc s limited Wrrnty covers only its Product, nd not ny relted items. 24