When it comes to selecting the support for your finished floors, typical plywood and traditional commodity oriented strand board (OSB) subflooring satisfy minimum standards in current building codes. Some experts suggest that 15/32-inch plywood should be standard if the underlying floor joists are spaced 16 inches apart or less, but slightly thicker 3/4-inch plywood should be used for joists spaced further apart. Practical use. Subfloor Plywood Aeroc Club Subfloor Plywood Aeroc Club 18. Chart represents most common plywood sheet sizes in inches (imperial system) and millimeters (metric dimensions). The spacing of the joists supporting the floor determines the plywood thickness. Oriented strand board, or OSB, is a wood structural panel that can also be used for flooring. *Most of plywood sheets available in different thicknesses. Bathroom Subfloor Wood Basement Bathroom Subfloor Wood Basement 20. Edge Gold Scant Face Tongue and Groove 23/32 CAT PS2-10 Tongue and Groove OSB Subfloor, Application as 4 x 8 Learn how your comment data is processed. Softwood plywood typically used for rough framing comes in 4 x 8 feet (1220 x 2438 millimeters) sheets. FORMALL panels are designed to provide superior For 23/32- and 3/4-inch panels, joists should be 24 inches on center. Click the image for larger image size and more details. Glue is sprayed between each layer and the sheet is hot pressed. For joist spans 16 inches or less, NWFA recommends minimum panel thickness of 5⁄8-inch plywood or 23⁄32-inch OSB; the building code requires 5⁄8-inch plywood or OSB. For 7/8-inch panels, joists can be up to 32 inches on center, and for 1 3/32- and 1 1/8-inch-thick panels, the joists can be spaced 48 inches on center. Floor joist spacing has traditionally been 24 inches on center, or from center to center of the joists. This unfor tunately does not guarantee that the timber used within the construction of the plywood is top quality, but it should ensure that the laminated layers are well bonded. But we want as thin as reasonable. The thickness of plywood panels in a subfloor is regulated by the spacing of the joists. Build up from the lowest elevation, using the products that allow for enough incremental elevation gain to get to within flatness tolerance. This number is known as a span rating. For 19/32-inch-thick panels, the joists should be 20 inches on center. Plywood. Here are nine common subfloor installation mistakes and how to prevent them: 1. Right now, I have 3/4 TG hardwood, which is not in the best shape, over a 2.5" wide x 3/4" inch think plank subfloor, which runs perpendicular to … In standard construction, subfloors are ¾ inch plywood or thicker. or 9.23.14.5.B. If just overboarding then a minimum 6mm thickness is required. Hi homework911, It will depend on the type of sub-floor you have and the thickness of the materials you're using. Hardwood Floors Plywood Yes Hometalk Hardwood Floors Plywood Yes Hometalk. The thicknesses are as follows: 7/16-, 15/32- and 1/2-inch-thick panels require joists spaced 16 inches on center; 19/32- and 5/8-inch-thick panels require joists spaced 20 inches on center. Benefits of our 1/2″ plywood include lighter weight, lower cost, and an extra ¼ inch of headroom! Tile over Wood Subfloor. Subfloor holds up all of the above layers of flooring, as well as everything in your house—people, dogs, cats, pianos, furniture. For 7/8-inch panels, joists can be up to 32 inches on center, and for 1 3/32- and 1 1/8-inch-thick panels, the joists can be spaced 48 inches on center. 2. You should not have the sunken flooring issue again. Plywood is often sold with a nominal thickness of 1/4 “, 1/2” or 3/4 “, but the original thickness is often 1/32” thick. 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