20163602 - Permit (2) - Laserfiche WebLink

Home Browse Search

Rafter Spacing Roof Slope 16" o.c 24" o.c 32" o.c. Photovoltaic Arrays (4 psf max) Flat to 6:12 0" to 26'5'-4"6' -O'5'4" 1.'-4"2' O"1' -Q"7 t72 lo 72:72 77' lo 45' 13:L2 to 24:L2 46' to 63'z-u 2'-8" Solar Thermal Arrays (5 psf max) 4' -0"5' -4"Flat to 6:12 0" to 26"4'-Q" 7:12 to 72.72 27' to 45"L'-4"z',-0"2',-8" 13.L2 lo 24:L2 46" to 63"Calc. Req'd Ca lc. Req'd Calc. Req'd Table 1. Maximum Horizont lAnchor Spachg 2 3 Solar support component manuJacturer's guidelines may be relied upon to ensure lhe array above the roof is properly designed, but manufacturer\ guidelines typically do NOT check to ensure that lhe roof itself can support the concentrated loads from lhe solar array. Table I assumes that the roof complied with the building code in eIJect at the time of construclion, and places limits on anchor horizontal spacing lo ensure that a roof structure is not overloaded under either downward loads or wind uplift loads. Note 4 below lists the basic assumptions upon which this table is based. Table I Notes Anchors are also known as "stand-offs," "feet," "mounts" or "points of attachment." Horizontal anchor spacing is also known as'tross-slope" or "east-west" anchor spacing (see Figure 2). If anchors are staggered from row'to-row going up the roof, the anchor spacing may be twice that shown above, but no greater than 6'-0'l For manufactured plated wood trusses at slopes of flat to 6:12, the horizontal anchor spacing shall not exceed 4'-0" and anchors in adjacent rows shallbe staggered. This table is based on the following assumptions: . The roofstructure conformed to building code requirements at the time it was built. . The attached list ofcriteria is met. . Mean roofheight is not greater than 40 feet. . Roofsheathing is at least 7/l6" thick oriented strand board or ply,r,vood. lx skip sheathing is acceptable. . Ifthe dwelling is in Wind Exposure B (typical urban, suburban or wooded areas farther than 500 yards from large open fields), no more than one of the following conditions apply: - The dwelling is located in a Special Wind Region with design wind speed between I l5 and 130 mph per ASCE 7-10. - The dwelling is located on the top halfofa tall hill, provided average slope is less than l5%. .lfthedwellingisinWindExposureC(within500yardsoflargeopenfieldsorgrasslands),all ofthe following conditions apply. - Design wind speed is I l0 mph or less (not in a Special Wind Region). - The dwelling is not located on the top halfofa tall hill. . The solar array displaces roof live loads (temporary construction loads) that the roof was originally designed to carry. . The Structural Technical Appendix provides additional information about analysis assumptions. .1 7'-4"