SPS 327.31(8)(a)(a)
Plywood sheathing. Plywood sheathing used for floors shall be limited to the allowable loads and spans shown in Table 327.31-A.
SPS 327.31(8)(b)
(b)
Combination subfloor-underlayment. Combination subfloor-underlayment shall be installed in accordance with Table 327.31-B.
SPS 327.31(8)(c)
(c)
Floor boards. Where wood boards are used for floor sheathing, the boards shall comply with the minimum thicknesses shown in Table 327.31-C.
SPS 327.31(8)(d)
(d)
Planks. Planks shall be tongue and groove or splined and at least 2 inches, nominal, in thickness. Planks shall terminate over beams unless the joints are end matched. The planks shall be laid so that no continuous line of joints will occur except at points of support. Planks shall be nailed to each beam.
SPS 327.31(9)(a)(a)
Sawn lumber. Bridging shall be provided for sawn lumber framing at intervals not exceeding 8 feet where the nominal depth to thickness ratio is greater than 4 to 1.
SPS 327.31 Note
Note: This 4:1 ratio means bridging is required for wood-framed floors having nominal 2X10 or deeper solid-sawn-lumber joists, to provide restraint against rotation or lateral displacement.
SPS 327.31(9)(b)
(b)
Engineered products. Bridging shall be provided for engineered framing products in accordance with the manufacturer's recommendations.
SPS 327.31(10)
(10) Sill plates. All of the following requirements apply to a sawn-lumber sill plate with uniform loading that is partially extended beyond the load-bearing surface of a foundation wall in order to put the exterior surface of an upper-lying wall flush with or beyond the exterior surface of insulation that is placed on the outside of the foundation wall:
SPS 327.31(10)(a)
(a) The center of any anchor bolt shall be set back from the side edge of the sill plate by a distance of at least 4 times the diameter of the bolt.
SPS 327.31(10)(b)
(b) The thickness of the concrete or mortar cover around any anchor bolt shall comply with ACI 318 section 7.7.
SPS 327.31 Note
Note: Under ACI 318 section 7.7, the minimum cover for a 5/8-inch-diameter or smaller bolt is 1 1/2 inches.
SPS 327.31(10)(c)
(c) With wood floor joists that are parallel to the foundation wall, the sill plate may not extend beyond the load-bearing surface of the wall by more than one-half of the nominal thickness of the joist that bears on the sill plate.
SPS 327.31(10)(d)
(d) As used throughout this subchapter and in the standards that the subchapter incorporates by reference, the shorter side of the cross-sectional area of a wood member is the thickness of the member. The longer side of the cross-sectional area is the depth, when the longer side is vertical; and it is the width when the longer side is horizontal.
SPS 327.31 Note
Note: Under sub. (6), wood floor joists that are perpendicular to the foundation wall can extend beyond the foundation wall by a distance of up to the depth of the joist.
Table 327.31-A
ALLOWABLE SPANS FOR PLYWOOD FLOOR SHEATHING CONTINUOUS OVER TWO OR
MORE SPANS AND FACE GRAIN PERPENDICULAR TO SUPPORTS1
Span Rating2 Plywood Thickness Maximum span3
32/16 15/32”, 1/2”, 5/8” 16”5
40/20 19/32”, 5/8”, 3/4”, 7/8” 20”
4,5
48/24 23/32”, 3/4”, 7/8” 24”
1 These values apply to C-D, C-C, and Structural I and II grades only. Spans shall be limited to values shown because of possible effect of concentrated loads.
2 Span Rating appears on all panels in the construction grades listed in footnote 1.
3 Plywood edges shall have approved tongue and groove joints or shall be supported with blocking, unless 1/4 inch minimum thickness underlayment or 1 1/2 inches of approved cellular or lightweight concrete is installed or finished floor is 25/32-inch wood strip. Allowable uniform load based on deflection of 1/360 of span is 165 pounds per square foot.
4 For joists spaced 24 inches on center, plywood sheathing with Span Rating 40/20 or greater can be used for subfloors when supporting 1 1/2 inches lightweight concrete.
5 May be 24 inches if 25/32-inch wood strip flooring is installed at right angles to joists.
Table 327.31-B
MINIMUM THICKNESS FOR PLYWOOD COMBINATION
SUBFLOOR-UNDERLAYMENT. PLYWOOD CONTINUOUS OVER TWO OR MORE
SPANS AND FACE GRAIN PERPENDICULAR TO SUPPORTS1,2
Maximum Support Spacing3
16” o.c 20” o.c 24” o.c
Plywood Panel Panel Panel
Species Thickness Thickness Thickness
Plywood Grade Group (inches) (inches) (inches)
Sanded exterior type 1 1/2 5/8 3/4
2 & 3 5/8 3/4 7/8
4 3/4 7/8 1
Underlayment C-C All Groups APA Rated Sheathing and APA Rated
Plugged Sturd-I-Floor4 Sturd-I-Floor shall be installed consistent
with their rating.
1 Spans shall be limited to values shown, based on possible effect of concentrated loads.
2 Unsupported edges shall be tongue and groove or blocked except where 1/4 inch underlayment or 25/32-inch finish floor is used.
3 Underlayment, C-C Plugged, sanded exterior type: allowable uniform load based on deflection of L/360 span for spans 24 inches or less is 125 psf; and for spans 48 inches, 65 psf.
4 The department will accept subfloor underlayment panels such as Sturd-I-Floor which meet the requirements of APA manufacturing specifications for Sturd-I-Floor panels.
Table 327.31-C
MINIMUM THICKNESS OF FLOOR BOARDS
Minimum Net Thickness
Joist Spacing Perpendicular to Joist Diagonal to Joist
24” 11/16” 3/4”
16” 5/8” 5/8”
SPS 327.31 History
History: EmR1703: emerg. cr., eff. 2-6-17;
CR 17-017: cr.
Register March 2018 No. 747, eff. 4-1-18; (6) (d) (title) created under s.
13.92 (4) (b) 1., Stats.,
Register March 2018 No. 747.
SPS 327.32
SPS 327.32 Decks. A deck attached to a camping unit or any detached deck that serves an exit from a camping unit that meets the following requirements is in compliance with this code:
SPS 327.32(1)
(1) A deck shall be constructed to support the actual dead load and a minimum live load of 40 pounds per square inch acting on it without exceeding the allowable stresses of the material.
SPS 327.32(2)
(2) A deck attached to a camping unit shall have a ledger attachment that meets the requirement under
sub. (1).
SPS 327.32(3)
(3) Corrosion-resistant flashing shall be installed where a deck attaches to the wall or floor assembly of a camping unit.
SPS 327.32 History
History: EmR1703: emerg. cr., eff. 2-6-17;
CR 17-017: cr.
Register March 2018 No. 747, eff. 4-1-18.
SPS 327.33(1)
(1)
General. The exterior walls shall be covered with a permanent weather resistant finish.
SPS 327.33(2)
(2) During construction. During construction, wall cavity insulation may not be installed until a water-resistant covering is in place over the wall cavity and windows, doors and a roof with at least underlayment are installed.
SPS 327.33 Note
Note: An example of acceptable water-resistant covering for a wall is foam sheathing with permanently taped joints.
SPS 327.33(3)(a)(a) Corrosion-resistant flashing shall be installed in the exterior wall to prevent water from entering the wall cavity or coming in contact with the structural framing components.
SPS 327.33(3)(b)
(b) The flashing shall extend to the surface of the exterior wall finish and prevent water from reentering the exterior wall.
SPS 327.33(3)(c)1.1. Any joints between 2 pieces of flashing that form a vertical joint shall be lapped a minimum of 6 inches and sealed.
SPS 327.33(3)(c)2.
2. Any joints between 2 pieces of flashing that form a horizontal joint shall be lapped a minimum of 2 inches and sealed unless otherwise specified by the flashing manufacturer.
SPS 327.33(3)(c)3.
3. Sealants used for flashing shall be exterior grade and shall be compatible with the materials being sealed.
SPS 327.33(3)(d)
(d) Flashing shall be provided at all of the following locations:
SPS 327.33(3)(d)1.
1. At the top of all exterior door and window openings, unless using self-flashing windows that provide at least one inch of flashing around the opening, including the corners.
SPS 327.33(3)(d)2.
2. At the intersection of chimneys or other masonry construction with frame walls.
SPS 327.33(3)(d)5.
5. Where porches, decks, or stairs attach to a wall or floor assembly of wood frame construction.
SPS 327.33 Note
Note: Flashing placed along the bottom of a door opening that is elevated above-grade can subsequently accommodate adding a deck outside the door.
SPS 327.33(3)(e)
(e) For a roof that intersects with an upper-lying head wall and rake wall, such as where a dormer is provided, the vertical metal flashing along the rake wall shall extend down the roof at least one-half inch past the vertical flashing on the head wall.
A head wall as addressed in this paragraph intersects a sloping roof at a horizontal line along the top of a roof segment. A rake wall intersects a sloping roof along the side of a roof segment.
SPS 327.33(3)(f)
(f) For a roof eave that intersects with a sidewall, the end of the roof flashing shall be installed so that it diverts water away from the sidewall and onto the roof or into the gutter.
SPS 327.33(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 327.33 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 materials will not result in a permanently taped joint.
SPS 327.33(4)(a)2.
2. Structural products with an integral water-resistive barrier may be approved as a complete assembly.
SPS 327.33(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 327.33 Note
Note: Spray-applied water-resistive barriers may not be compatible with foam plastic insulation.
