Wis. Admin. Code Department of Safety and Professional Services SPS 321.10

Current through October 28, 2024
Section SPS 321.10 - Protection against decay and termites
(1) Wood used in any of the applications under this section shall meet all of the following requirements:
(a) The wood shall be labeled and pressure treated with preservative in accordance with an AWPA standard or shall be naturally durable and decay-resistant or shall be engineered to be decay resistant.
(b) The wood shall be pressure treated with preservative or shall be naturally termite-resistant unless additional steps are taken to make the wood termite-resistant.
(2) Wood used in the following locations shall be as required under sub. (1):
(a) Resting directly upon or embedded in earth.
(b) Floor joists or sleepers that meet all of the following conditions:
1. The joists or sleepers are protected from the weather.
2. The joists or sleepers are within 18 inches above a lower floor surface, deck or soil.
3. There is no vapor retarder that meets the requirements under s. SPS 322.38(1) (a) between the joists or sleepers and the soil below.

Note: This situation could occur with a floor over a crawl space or when a floor is added over a patio deck or a garage slab.

(c) Floor joists exterior to the dwelling that are within 18 inches above exterior grade, unless protected with a moisture barrier.

Note: Acceptable moisture barriers for this application include 3/4-inch exterior preservative-treated plywood, or ice dam protection material listed as meeting the requirements of ASTM D 1970 or vapor retarder material, provided they are protected from physical and UV light damage.

(d) Girders that span directly over and within 12 inches of earth.
(e) Sills and rim joists that rest on concrete or masonry and are also below grade or within 8 inches above final exterior grade.
(f)
1. Siding and sheathing in contact with concrete, masonry or earth and within 6 inches above final exterior grade.
2. Siding and sheathing in contact with concrete or masonry and within 2 inches above an impervious surface.
(g) Ends of wood structural members and their shims resting on or supported in masonry or concrete walls and having clearances of less than 1/2 inch on the top, sides and ends.
(h) Bottom plates or sole plates of walls that rest on concrete or masonry and that are below exterior grade or less than 8 inches above final exterior grade.
(i) Columns in direct contact with concrete or masonry unless supported by a structural pedestal or plinth block at least one inch above the floor.
(j) Any structural part of an outdoor deck, including the decking.
(k) Permanent wood foundations.
(3) Wood girders that rest directly on exterior concrete or masonry shall be protected by one of the following methods:
(a) The wood shall be pressure treated with preservative or shall be a naturally durable and decay-resistant species.
(b) Material, such as pressure-treated plywood, flashing material, steel shims, or water-resistant membrane material shall be placed between the wood and the concrete or masonry.
(4) All pressure-treated wood and plywood shall be identified by a quality mark or certificate of inspection of an approved inspection agency which maintains continued supervision, testing and inspection over the quality of the product.

Note: Heartwood of redwood, cypress, black walnut, catalpa, chestnut, sage orange, red mulberry, white oak, or cedar lumber are considered by the department to be naturally decay-resistant. Heartwood of bald cypress, redwood, and eastern red cedar are considered by the department to be naturally termite resistant.

(5) FASTENERS.
(a) Fasteners for pressure-preservative treated wood and fire-retardant-treated wood shall meet one of the following requirements:
1. The fastener is a steel bolt with a diameter of 0.5 inch or greater.
2. The fastener is made of stainless steel.
3. The fastener is made of hot-dipped, zinc-galvanized steel with the coating weight and thickness labeled as complying with ASTM A 153.
4. The fastener is made of steel with a mechanically-deposited zinc coating labeled as complying with ASTM B 695, Class 55 or greater.
5. The fastener has coating types and weights in accordance with the fastener manufacturer's recommendations. In the absence of the manufacturer's recommendations subd. 1., 2., 3., or 4. shall apply.

Note: "Zinc plated," "zinc coated," "chrome plated," etc., fasteners do not necessarily comply with either of these standards.

(b) When a fastener is used with a hanger or other metal fixture, the fastener shall be of the same material as the hanger or metal fixture.

Note: When separate pieces are in close contact, zinc corrodes rapidly in the presence of plain steel. Zinc corrodes much more rapidly in the presence of stainless steel.

(c) For the purposes of this section, a fastener includes nails, screws and bolts, along with nuts and washers.

Wis. Admin. Code Department of Safety and Professional Services SPS 321.10

Cr. Register, November, 1979, No. 287, eff. 6-1-80; r. and recr. Register, February, 1985, No. 350, eff. 3-1-85; am. (1) (b) and (3), Register, January, 1989, No. 397, eff. 2-1-89; r. and recr. (1) (intro.) and (b), am. (1) (f), renum. (3) (intro.) to be (3) (a), cr. (3) (b), Register, March, 1992, No. 435, eff. 4-1-92; am. (1) (a), (b), (3), cr. (1) (g), Register, November, 1995, No. 479, eff. 12-1-95; r. (1) and (2), renum. (3) to be (4), and cr. (1) to (3), Register, March, 2001, No. 543, eff. 4-1-01; CR 02-077: am. (4) (a) Register May 2003 No. 569, eff. 8-1-03; CR 08-043: am. (1), (2) (a) and (i), r. and recr. (2) (b) and (h), r. (2) (g) and (4) (b), renum. (2) (c) to (f) and (4) (a) to be (2) (d) to (g) and (4) and am. (2) (e), (f) 1. and (g), cr. (2) (c), (k) and (5) Register March 2009 No. 639, eff. 4-1-09; correction in (2) (a) 3. made under s. 13.92(4) (b) 7, Stats., Register March 2009 No. 639; correction in (2) (b) 3. made under s. 13.92(4) (b) 7, Stats., Register December 2011 No. 672.
Amended by, CR 15-041: renum. (2) (f) to (2) (f) 1., cr. (2) (f) 2. Register December 2015 No. 720, eff.1/1/2016