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Expedited Permit Process for PV Systems Expedited Permit Process for PV Systems The information in this guideline is intended to help local jurisdictions and contractors identify when PV system installations are simple, needing only a basic review, and when an installation is more complex. It is likely that 50%-75% of all residential systems will comply with these simple criteria. For projects that fail to meet the simple criteria, resolution steps have been suggested to provide as a path to permit approval. Required Information for Permit: 1. Site plan showing location of major components on the property. This drawing need not be exactly to scale, but it should represent relative location of components at site (see supplied example site plan). PV arrays on dwellings with a 3’ perimeter space at ridge and sides may not need separate fire service review. 2. Electrical diagram showing PV array configuration, wiring system, overcurrent protection, inverter, disconnects, required signs, and ac connection to building (see supplied standard electrical diagram). 3. Specification sheets and installation manuals (if available) for all manufactured components including, but not limited to, PV modules, inverter(s), combiner box, disconnects, and mounting system. 6WHS Is the array to be mounted on a defined, permitted roof structure? NYes N No If No due to non-compliant roof or a ground mount, submit completed worksheet for the structure WKS1. Roof Information: 1. Is the roofing type lightweight (Yes = composition, lightweight masonry, metal, If No, submit completed worksheet for roof structure WKS1 (No = heavy masonry, slate, etc…). 2. Does the roof have a single roof covering? NYes N No If No, submit completed worksheet for roof structure WKS1. 3. Provide method and type of weatherproofing roof penetrations (e.g. flashing, Mounting System Information: 1. Is the mounting structure an engineered product designed to mount PV modules? N Yes N No If No, provide details of structural attachment certified by a design professional. 2. For manufactured mounting systems, fill out information on the mounting system below: a. Mounting System Manufacturer Name and b. Total Weight of PV Modules and Rails c. Total Number of Attachment d. Weight per Attachment Point (if greater than 45 lbs, see WKS1) e. Maximum Spacing Between Attachment Points on a Rail (see product manual for maximum spacing allowed based on maximum design wind speed) f. Total Surface Area of PV Modules (square ft2 g. Distributed Weight of PV Module on Roof lbs/ft2 If distributed weight of the PV system is greater than 5 lbs/ft2, see WKS1 6WHS In order for a PV system to be considered for an expedited permit process, the following must apply: 1. PV modules, utility-interactive inverters, and combiner boxes are identified for use in PV systems. 2. The PV array is composed of 4 series strings or less per inverter, and 15 or less. 3. The total inverter capacity has a continuous ac power output 13,440 Watts or less 4. The ac interconnection point is on the load side of service disconnecting means (690.64(B)). 5. The electrical diagram (E1.1) can be used to accurately represent the PV system. Fill out the standard electrical diagram completely. A guide to the electrical diagram is provided to help the applicant understand each blank to fill in. If the electrical system is more complex than the standard electrical diagram can effectively communicate, provide an alternative diagram with appropriate detail. ✔ ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- 51 Solar America Board for Codes and Standards Report APPENDIX B: STRUCTURAL B.1 Structure Worksheet—WKS1 If array is roof mounted This section is for evaluating roof structural members that are site built. This includes rafter systems and site built trusses. Manufactured truss and roof joist systems, when installed with proper spacing, meet the roof structure requirements covered in item 2 below. 1. Roof construction: l Rafters l Trusses l Other: 2. Describe site-built rafter or or site-built truss system. a. Rafter Size: x inches b. Rafter Spacing: inches c. Maximum unsupported span: feet, inches d. Are the rafters over-spanned? (see the IRC span tables in B.2.) l Yes l No e. If Yes, complete the rest of this section. 3. If the roof system has a. over-spanned rafters or trusses, b. the array over 5 lbs/ft2 on any roof construction, or c. the attachments with a dead load exceeding 45 lbs per attachment; it is recommended that you provide one of the following: i. A framing plan that shows details for how you will strengthen the rafters using the supplied span tables in B.2. ii. Confirmation certified by a design professional that the roof structure will support the array. If array is ground mounted: 1. Show array supports, framing members, and foundation posts and footings. 2. Provide information on mounting structure(s) construction. If the mounting structure is unfamiliar to the local jurisdiction and is more than six feet above grade, it may require engineering calculations certified by a design professional. 3. Show detail on module attachment method to mounting structure. ---PAGE BREAK--- Expedited Permit Process for PV Systems 52 B.2 Span Tables A framing plan is required only if the combined weight of the PV array exceeds 5 pounds per square foot (PSF or lbs/ft2) or the existing rafters are over-spanned. The following span tables from the 2009 International Residential Code (IRC) can be used to determine if the rafters are over-spanned. For installations in jurisdictions using different span tables, follow the local tables. Span Table R802.5.1(1), Use this table for rafter spans that have conventional light-weight dead loads and do not have a ceiling attached. 10 PSF Dead Load Roof live load = 20 psf, ceiling not attached to rafters, L/∆=180 Rafter Size 2 x 4 2 x 6 2 x 8 2 x 10 2 x 12 Spacing (inches) Species Grade The measurements below are in feet-inches (e.g. 9-10 = 9 feet, 10 inches). 16 Douglas Fir-larch #2 or better 9-10 14-4 18-2 22-3 25-9 16 Hem-fir #2 or better 9-2 14-2 17-11 21-11 25-5 24 Douglas Fir-larch #2 or better 8-0 11-9 14-10 18-2 21-0 24 Hem-fir #2 or better 7-11 11-7 14-8 17-10 20-9 Use this table for rafter spans that have heavy dead loads and do not have a ceiling attached. 20 PSF Dead Load Roof live load = 20 psf, ceiling not attached to rafters, L/∆=180 Rafter Size 2 x 4 2 x 6 2 x 8 2 x 10 2 x 12 Spacing (inches) Species Grade The measurements below are in feet-inches (e.g. 9-10 = 9 feet, 10 inches). 16 Douglas Fir-larch #2 or better 8-6 12-5 15-9 19-3 22-4 16 Hem-fir #2 or better 8-5 12-3 15-6 18-11 22-0 24 Douglas Fir-larch #2 or better 6-11 10-2 12-10 15-8 18-3 24 Hem-fir #2 or better 6-10 10-0 12-8 15-6 17-11 ---PAGE BREAK--- 53 Solar America Board for Codes and Standards Report Span Table R802.5.1(2), Use this table for rafter spans with a ceiling attached and conventional light-weight dead loads. 10 PSF Dead Load Roof live load = 20 psf, ceiling attached to rafters, L/∆=240 Rafter Size 2 x 4 2 x 6 2 x 8 2 x 10 2 x 12 Spacing (inches) Species Grade The measurements below are in feet-inches (e.g. 9-10 = 9 feet, 10 inches). 16 Douglas Fir-larch #2 or better 8-11 14-1 18-2 22-3 25-9 16 Hem-fir #2 or better 8-4 13-1 17-3 21-11 25-5 24 Douglas Fir-larch #2 or better 7-10 11-9 14-10 18-2 21-0 24 Hem-fir #2 or better 7-3 11-5 14-8 17-10 20-9 Use this table for rafter spans with a ceiling attached and where heavy dead loads exist. 20 PSF Dead Load Roof live load = 20 psf, ceiling attached to rafters, L/∆=240 Rafter Size 2 x 4 2 x 6 2 x 8 2 x 10 2 x 12 Spacing (inches) Species Grade The measurements below are in feet-inches (e.g. 9-10 = 9 feet, 10 inches). 16 Douglas Fir- larch #2 or better 8-6 12-5 15-9 19-3 22-4 16 Hem-fir #2 or better 8-4 12-3 15-6 18-11 22-0 24 Douglas Fir- larch #2 or better 6-11 10-2 12-10 15-8 18-3 24 Hem-fir #2 or better 6-10 10-0 12-8 15-6 17-11 Use the conventional light-weight dead load table when the existing roofing materials are wood shake, wood shingle, composition shingle, or light-weight tile. (The rationale for allowing these tables to be used is that the installation of a PV system should be considered as part of the live load, since additional loading will not be added to the section of the roof where a PV array is installed.) Where heavy roofing systems exist (e.g. clay tile or heavy concrete tile roofs), use the 20 lbs/ft2 dead load tables.