What Plywood To Use For Roof Decking

X stands for exterior use.

What plywood to use for roof decking.

The thickness of plywood used for roof decking depends on the roof slope the spacing of rafters and the weight of other material to be put over the decking as well as the design load the. Sheet with varying thickness. Cdx plywood is a construction grade type of plywood that is designed for exposure to the elements. This kind of plywood can be used on roofs with minimal load.

It can withstand moisture for a brief period of time but may become warped and delaminated with consistent exposure to the elements. Plank sheathing usually 1 6 or 1 8 was used as a roof deck before plywood. In the u s roof sheathing is almost always composed of wood usually osb oriented strand board or plywood. Multi ply is a catchall term for plywood with seven or more plies.

As a quick primer in plywood each side is rated from a to d. Osb and plywood come in thicknesses ranging from 5 16 to 3 4 inch and the thickness needed for a particular roof depends on several factors including rafter spacing expected load and roof design. Required dimensions of plywood for roofing. Plywood typically comes in 4 8 ft.

The sole exception to this is pressure treated cdx which can survive for decades without even a protective coating. The common grade of plywood for roof sheathing is cdx. Steeper rather than flatter roofs will have lesser load per sq. The industry offers a thickness of anywhere from 5 16 inch to inch.

In the first half of the 20th century roofs in missouri were built with wood shingles over planks spaced about 1 apart. Osb is lightweight relatively inexpensive and strong enough to resist bending or breaking should someone walk on the roof. Roof sheathing or decking is one of those elements. Do not use cdx for roofing sheds or other places that are exposed to moisture consistently.

Foot and with a maximum of spacing of. Look for something that s graded as exposure 1 or exterior. In addition to the thickness you also need to make sure that you choose plywood that s graded for outdoor use. Use it indoors or outdoors but avoid using for framing permanent structures such as a shed or a home.

A is smooth and knot free while d the lowest quality has missing knots and cracks. What size plywood should you use for your roof. The minimum thickness of plywood used for roofing is 3 8 th of an inch. It should be placed up on the roof.

Only use cdx plywood for the interior of a house where water damage is far less likely. One side is usually better quality than the other c in this case. This plywood is strong and durable enough for use in roofing framing and other exterior structural. What plywood should you use for a roof.