Section SPS 321.28 - Weather protection for roofs(1) GENERAL. (a) All roofs shall be designed and constructed to assure drainage of water(b) All fasteners shall be corrosion resistant.(2) UNDERLAYMENT FOR SHINGLES. Underlayment consisting of number 15 asphalt-impregnated felt paper or equivalent or other type I material that shows no water transmission when tested in accordance with ASTM D 226 or ASTM D 4869 shall be provided under shingles. Note: Underlayment materials meeting the requirements of ASTM D 1970 meet the performance requirements of this section.
(3) ASPHALT SHINGLES. (a)General. 1. Shingles that have a self-sealing adhesive strip shall include a sealant which has an average bond strength of at least 1.5 pounds per 3.75 inches of shingle width, at 32 °F. Note: The department will accept results of testing conducted in accordance with an approved test method for verifying compliance with the sealant uplift resistance required in this paragraph. Information on the applicable test method may be obtained from the department.
2. Each shingle package shall be labeled by the manufacturer to indicate conformance to the applicable ASTM standard for each type of shingle or the exception in par (c).3. Shingles shall be installed in accordance with the manufacturer's recommendations.4. Shingles shall have at least 4 fasteners per strip shingle or 2 fasteners per interlocking shingle, unless the manufacturer has other specifications.5. Shingle head lap shall be at least 2 inches, unless the manufacturer has other specifications.6. All fasteners for shingles shall be corrosion-resistant. Note: See s. SPS 320.07(62) for definitions of shingle terms.
Note: Section SPS 320.04(2) requires compliance with all parts of this code, including these roofing provisions, for an alteration to any dwelling that is regulated under this code.
(c)Fiberglass shingles. Fiberglass asphalt shingles shall conform to ASTM D 3462 except that laminated shingles shall have a tear strength of at least 1450 grams in each ply.(4) ICE DAM PROTECTION. (a) Shingled or shake roofs that extend over a heated area of a dwelling or attached garage and that have a slope of 4:12 or less shall be provided with ice dam protection in the form of sheet metal or a product labeled as meeting the requirements of ASTM D 1970.(b) The ice dam protection shall extend at least 30 inches up the roof slope from the roof edge and at least 12 inches up the roof slope beyond the inner face of the exterior wall.(5) OTHER ROOF COVERINGS. All roof coverings not otherwise addressed in this section shall be installed in accordance with the manufacturer's instructions or a national standard recognized by the department.(6) REROOFING. New roof coverings may not be installed over existing roof coverings where any of the following conditions exist:(a) The existing roof or roof covering is water-soaked or has deteriorated such that it is inadequate as a base for additional roofing.(b) The existing roof is wood shake, slate, clay, cement or asbestos-cement tile.(c) The existing roof has 2 or more applications of any type of permanent roof covering.(7) FLASHING. (a)General. Flashing shall be installed at the junction of chimneys and roofs, in all valleys, and around all roof openings.(b)Flashing of open valleys. 1. Open valleys shall be flashed with at least No. 28 gauge corrosion-resistant sheet metal, 16 inches wide, or a layer of at least 50-pound roll roofing, 16 inches wide, placed over a layer of number 15 roofing underlayment.2. Flashing sections shall be overlapped by at least 4 inches.(c)Flashing of closed valleys. Where shingles are laced or woven over the valley, the valley shall be flashed with one of the following: 1. At least one layer of 50-pound roofing, at least 20 inches wide, over a layer of number 15 roofing underlayment.2. A product labeled as meeting the requirements of ASTM D1970.(d)Chimney flashing. 1. Chimneys shall be flashed and counter-flashed to a height of at least 6 inches. 2. Chimney crickets or saddles shall be installed where the upper side of a chimney is more than 30 inches wide on a sloping roof.3. The intersection of the cricket and the chimney shall be flashed and counter-flashed to a height of at least 6 inches.Wis. Admin. Code Department of Safety and Professional Services SPS 321.28
Cr. Register, November, 1979, No. 287, eff. 6-1-80; am. (7) (a), r. and recr. Table 321.28-A, Register, January, 1989, No. 397, eff. 2-1-89; am. (1), (5) and (6), cr. (2m) and (6) (a) 3., r. and recr. (4) (c), Register, March, 1992, No. 435, eff. 4-1-92; cr. (6) (c), Register, November, 1995, No. 479, eff. 12-1-95; CR 02-077: r. and recr. (1) (a), renum. (6) (intro) to (c) to be (6) (a) to (d) and am. (6) (a) to (c) Register May 2003 No. 569, eff. 8-1-03; CR 08-043: r. and recr. Register March 2009 No. 639, eff. 4-1-09.Amended by, CR 15-041: am. (3) (a) 2., cr. (3) (a) 6., r. (3) (b), renum. (7) (c) to (7) (c) (intro.) and 1. and am., cr. (7) (c) 2. Register December 2015 No. 720, eff. 1-1-16; correction in (3) (a) 2. under s. 13.92(4) (b) 7, Stats., Register December 2015 No. 720, eff.1/1/2016