Plywood Floor Sheathing Thickness

Plywood sheathing thickness jerry liebler posted in building code questions on june 6 2012 09 12am for a single floor residence is nominal 3 8 plywood acceptable sheathing on 10 foot tall walls built with 24 oc advanced framing.

Plywood floor sheathing thickness.

The recommended shed floor plywood thickness is 3 4 inch pressure treated exterior grade cdx plywood. Applicable to grade c c. The minimum thickness you need for standard 16 inch on centers joists is 5 8 inches but 3 4 inch plywood makes a more stable floor and is a. Usually these materials are either plywood or oriented strand board osb and are purchased in 4 by 8 foot sheets.

Sheathing over supports spaced up to 32 inches o c. Two sheets of 3 4 inch exterior grade plywood is the minimum accepted thickness for natural stone installations and if the stone is particularly heavy you may need to use floor joists that are 12 inches on center rather than the traditional 16. Applicable to all grades of sanded exterior type plywood. This type of plywood won t sag when used on a 12 inches joist structure.

Cdx plywood should be a minimum of 7 16 inch thick. See doc ps 1 for plywood species groups. Avoid using 1 2 inch plywood sheathing for a floor. The required span rating is affected by the spacing on your floor joists.

The wider the space between your joists the thicker your material must be as thicker material has a higher span rating. Or for floor sheathing over supports spaced up to 16 inches o c. It is rot resistant with knots replaced with football. Page 3 of 7 v1 0 01 2008 table b relationship between span rating and nominal thickness for plywood a nominal thickness b in span rating 3 8 7 16 15 32 1 2 19 32 5 8 23 32 3 4 7 8 1 1 1 8 sheathing span 24 0 0 375 0 437 0 469 0 500.

Floor panels conforming with this table shall be deemed to meet the design criteria of section 2304 7. Panel selection handling and storage table 2. Glue is sprayed between each layer and the sheet is hot pressed. Table r503 1 minimum thickness of lumber floor sheathing joist or beam spacing inches minimum net thickness perpendicular to joist diagonal to joist 24 11 16 3 4 16 5 8 5 8 48 a 1 1 2 t g.