SPS 321.24(3)(d)6. 6. At wall and roof intersections.
SPS 321.24(3)(d)7. 7. At built-in gutters.
SPS 321.24 Note Note: See s. SPS 321.26 (5) for additional flashing requirements with masonry cavity walls and s. SPS 321.28 (7) for additional flashing requirements with roofing.
SPS 321.24(4) (4)Water-resistive barrier requirements.
SPS 321.24(4)(a)(a) General.
SPS 321.24(4)(a)1.1. Exterior walls of wood or metal frame construction shall be provided with a water-resistive barrier from the highest point to the bottom of the permanent weather-resistant covering.
SPS 321.24 Note Note: Acceptable water-resistive barrier materials include polymeric-based house wraps and spray-applied water-resistive barriers installed per the manufacturer's instructions, #15 or greater asphalt-saturated felts that comply with ASTM D 226 for type I felt and extruded foam sheathing with permanently taped joints. Duct tape or similar will not result in a permanently taped joint.
SPS 321.24(4)(a)2. 2. Structural products with an integral water-resistive barrier may be approved by the department as a complete assembly.
SPS 321.24(4)(b) (b) Material compatibility. The water-resistive barrier material shall be compatible with the other materials in the wall with which it will come into contact.
SPS 321.24 Note Note: Spray-applied water-resistive barriers may not be compatible with foam plastic insulation.
SPS 321.24(4)(c) (c) Performance requirements.
SPS 321.24(4)(c)1.1. Polymer-based house wraps shall meet all of the following requirements:
SPS 321.24(4)(c)1.a. a. A water vapor permeability rating of 5 perms or higher when tested in accordance with ASTM E96.
SPS 321.24(4)(c)1.b. b. An acceptable water-resistance rating determined in accordance with ASTM D779, AATCC 127 or CCMC 07102.
SPS 321.24 Note Note: Asphalt-saturated felt or "tar paper" is not a polymeric-based house wrap.
SPS 321.24 Note Note: For more information on the water-resistance tests and their results, see the International Code Council Evaluation Services Acceptance Criteria AC 38.
SPS 321.24(4)(c)2. 2. Spray-applied water-resistive barriers shall be approved under the International Code Council Evaluation Services.
SPS 321.24 Note Note: For approval criteria, see ICC-ES acceptance criteria AC 212 or successor document.
SPS 321.24(4)(d) (d) Application.
SPS 321.24(4)(d)1.1. Horizontal seams in sheet or strip material shall be overlapped such that the upper layer extends over the lower layer at least 2 inches.
SPS 321.24(4)(d)2. 2. Vertical seams in sheet or strip materials shall be overlapped at least 6 inches.
SPS 321.24(4)(d)3. 3. Any rips, tears or voids shall be patched in accordance with subds. 1. and 2.
SPS 321.24(4)(e) (e) Penetrations.
SPS 321.24(4)(e)1.1. Penetrations caused by fasteners of the water-resistive barrier or the weather-resistant exterior covering do not require sealing.
SPS 321.24(4)(e)2. 2. Penetrations of 5 square inches or less with an annular space of no more than ½ inch shall be sealed with caulk or similar material.
SPS 321.24(4)(e)3. 3. Penetrations of greater than 5 square inches shall be flashed in accordance with sub. (3).
SPS 321.24 History History: Cr. Register, November, 1979, No. 287, eff. 6-1-80; r. and recr. Register, March, 2001, No. 543, eff. 4-1-01; CR 02-077: cr. (3) Register May 2003 No. 569, eff. 8-1-03; CR 08-043: am. (2), renum. (3) (c) to be (3) (d), cr. (3) (c) and (4) Register March 2009 No. 639, eff. 4-1-09.
SPS 321.25 SPS 321.25 Wood frame walls. Unless designed through structural analysis, wood frame walls shall comply with the following requirements.
SPS 321.25(1) (1)Stud configuration. Wood studs shall comply with the size and spacing requirements indicated in Table 321.25-A. Studs in the exterior walls shall be placed with the wide faces perpendicular to the plane of the wall.
SPS 321.25 Note Note: See Appendix for acceptable nailing schedule.
SPS 321.25 Note Note: See s. SPS 321.10 for requirements on treating wood for decay and termite resistance.
SPS 321.25(2) (2)Top plates.
SPS 321.25(2)(a)(a) General. Except as allowed under subd. 3., top plates shall be provided and configured as follows:
SPS 321.25(2)(a)1. 1. Studs at bearing walls shall be capped with double top plates.
SPS 321.25(2)(a)2. 2. End joints in double top plates shall be offset at least 2 stud spaces.
SPS 321.25(2)(a)3. 3. Double top plates shall be overlapped at the corners and at intersections of partitions.
SPS 321.25(2)(a)4. 4. The plate immediately above the stud may have a joint only when directly over the stud.
SPS 321.25(2)(b) (b) Notching and boring.
SPS 321.25(2)(b)1.1. When piping or ductwork is placed in an exterior wall or an interior load-bearing wall, such that at least half of the top plate is removed, the plate shall be reinforced with a steel angle at least 2 inches by 2 inches by 20 gauge thick.
SPS 321.25 Note Note: 20 gauge is approximately 0.036 inch.
SPS 321.25(2)(b)2. 2. The steel angle shall span the gap and extend at least to the midpoint of the adjacent stud spaces.
SPS 321.25(2)(b)3. 3. Other equivalent materials may be used in accordance with s. SPS 321.02.
SPS 321.25(2)(c) (c) Exceptions.
SPS 321.25(2)(c)1.1. A single top plate may be used in place of a double top plate provided a rafter is located directly over the studs and the plate is securely tied at the end joints, corners and intersecting walls. Joints may occur in single top plates only when directly over a stud.
SPS 321.25(2)(c)2. 2. A continuous header, consisting of two 2-inch members set on edge, may be used in lieu of a double plate if tied to the adjacent wall.
SPS 321.25(3) (3)Wall openings. Where doors or windows occur, headers shall be used to carry the load across the opening.
SPS 321.25(3)(a) (a) Header size. The size of headers shall be determined in accordance with the spans and loading conditions listed in Tables 321.25-B, 321.25-C and 321.25-D. Headers for longer spans shall be designed by an engineering method under s. SPS 321.02.
SPS 321.25(3)(b) (b) Header support. Headers in bearing walls shall be supported in accordance with subd. 1. or 2. or 3.
SPS 321.25(3)(b)1. 1. Headers 3 feet or less in length shall be directly supported on each end by either:
SPS 321.25(3)(b)1.a. a. The single common stud and a shoulder stud; or
SPS 321.25(3)(b)1.b. b. The single common stud with a framing anchor attached.
SPS 321.25(3)(b)2. 2. Headers greater than 3 feet but less than or equal to 6 feet in length shall be directly supported on each end by the single common stud and a shoulder stud.
SPS 321.25(3)(b)3. 3. Headers greater than 6 feet in length shall be directly supported on each end by the single common stud and 2 shoulder studs.
SPS 321.25(4) (4)Notching. Notching and boring of columns or posts is prohibited unless designed through structural analysis. Studs shall not be cut or bored more than 1/3 the depth of the stud, unless the stud is reinforced.
SPS 321.25(5) (5)Partitions. Load-bearing partitions shall be placed over beams, girders, or other load-bearing partitions. Load-bearing partitions running at right angles to the joists shall not be offset from the main girder or walls more than the depth of the joist unless the joists are designed to carry the load.
SPS 321.25(6) (6)Posts and columns.
SPS 321.25(6)(a)(a) General.
SPS 321.25(6)(a)1.1. Posts and columns shall be installed to resist imposed loads.
SPS 321.25(6)(a)2. 2. Posts and columns shall bear directly over the middle 1/ 3 of a footing.
SPS 321.25(6)(a)3. 3. Posts and columns shall be restrained at the top and bottom to resist displacement.
SPS 321.25(6)(a)4. 4. All columns shall be positively attached to the beams they support using clips, straps or saddles.
SPS 321.25(6)(a)5. 5. Posts and columns that use a height adjustment mechanism shall have the mechanism imbedded in concrete or permanently disabled after installation.
SPS 321.25(6)(b) (b) Bearing surface. Posts and columns shall have a steel bearing plate affixed to one or both ends to distribute any applied loads and to prevent fiber crushing of any structural member being supported.
SPS 321.25(6)(c) (c) Steel posts or columns. Steel posts or columns shall be sized according to one of the following methods:
SPS 321.25(6)(c)1. 1. Manufactured columns shall follow the manufacturer's testing and listing. - See PDF for table PDF
SPS 321.25 Note Note: A 3-story frame house with walls constructed of 2 x 4 standard grade studs would require a 12-inch stud spacing on the lowest level, a 24-inch stud spacing on the intermediate level, and a 24-inch stud spacing on the upper level.
SPS 321.25(6)(c)2. 2. Columns made solely of steel pipe stock shall follow Table 321.25-E.
SPS 321.25(6)(c)3. 3. Columns made of steel stock, not meeting the requirements of subd. 1.or 2., shall follow a nationally accepted design specification or the size shall be determined through structural analysis or load testing.
SPS 321.25(6)(d) (d) Wood posts or columns. Wood posts or columns shall be sized according to Table 321.25-F or the size shall be determined through structural analysis or load testing. - See PDF for table PDF - See PDF for table PDF - See PDF for table PDF
*These tables are based on wood with a fiber bending stress of 1,000 psi. For other species with different fiber bending stresses, multiply the span by the square root of the ratio of the actual bending stress to 1,000 psi. Example: From Table 321.25-B, the allowable roof/ceiling span for a 28-foot wide house in zone 2, using two 2 x 8 header members with a 1400 psi bending stress, is 5 feet - See PDF for diagram PDF = 5.9 feet. - See PDF for table PDF - See PDF for table PDF
SPS 321.25 Note Note: This Table is based on a modulus of elasticity or E of 1,000,000 psi and a fiber bending strength or Fb of 1,000 psi.
SPS 321.25(7) (7)foundation cripple walls.
SPS 321.25(7)(a)(a) Foundation cripple walls shall be framed with studs at least as large as the studs above.
SPS 321.25(7)(b) (b) When more than 4 feet in height, cripple walls shall be framed with studs needed for an additional floor level.
SPS 321.25(7)(c) (c) Cripple walls with a stud height of less than 14 inches shall be sheathed on at least one side for its entire length with a wood structural panel that is fastened to both the top and bottom plates or the cripple walls shall be constructed of solid blocking.
SPS 321.25(7)(d) (d) Cripple walls with a stud height of 14 inches or greater shall be braced in accordance with sub. (8).
SPS 321.25(7)(e) (e) Cripple walls shall be fully supported by a continuous foundation.
SPS 321.25(8) (8)Wall bracing.
SPS 321.25(8)(a)(a) General. Dwellings using wood-framed walls shall be braced in accordance with this section. Where a building, or a portion thereof, does not comply with one or more of the bracing requirements in this section, those portions shall be designed and constructed in accordance with accepted engineering practice.
SPS 321.25 Note Note: Acceptable engineering wall bracing practices include any of the following:
SPS 321.25 Note 1. The provisions under section R602.10 or R602.12 of the International Residential Code (IRC) – 2012.
SPS 321.25 Note 2. Design in accordance with the engineering basis of the 2012 IRC bracing provisions, such as described in Crandell, J. and Martin, Z., "The Story Behind the 2009 IRC Wall Bracing Provisions (Part 2: New Wind Bracing Requirements)," Wood Design Focus, Forest Products Society, Peachtree Corners, GA, Spring 2009.
SPS 321.25 Note 3. Installation instructions from the manufacturer of the bracing product that are compliant with section SPS 321.02.
SPS 321.25(8)(b) (b) Bracing Materials and Methods. Wall bracing shall consist of the materials and methods listed in Table 321.25–G or approved alternatives capable of providing the required wind load resistance as determined in accordance with s. SPS 321.02 (1) (c). - See PDF for table PDF - See PDF for table PDF
aThe interior side of all exterior walls shall be sheathed with minimum ½-inch gypsum wallboard unless otherwise permitted to be excluded by this subsection. All edges of panel-type wall bracing, except horizontal joints in GB bracing, shall be attached to framing or blocking.
bThe actual measured wall height shall include stud height and thickness of top and bottom plates. The actual wall height shall be permitted to exceed the listed nominal values by not more than 4½ inches. Tabulated bracing amounts in s. SPS 321.25 (8) (c) are based on a 10-foot nominal wall height for all bracing methods and shall be permitted to be adjusted to other nominal wall heights not exceeding 12 feet in accordance with footnotes to Table 321.25–I or Table 321.25–J.
cLIB is not permitted for walls supporting a roof and two floors. Two LIB braces installed at a 60o angle from horizontal shall be permitted to be substituted for each 45o angle LIB brace.
dBracing with CS-WSP and CS-SFB shall have sheathing installed on all sheathable surfaces above, below, and between wall openings.
dShall be attached to the top and bottom plates and any intermediate studs, in one continuous length.
Published under s. 35.93, Stats. Updated on the first day of each month. Entire code is always current. The Register date on each page is the date the chapter was last published.