Flat Roof Plywood Thickness

That s considered to be the minimum.

Flat roof plywood thickness.

A local roofer submitted a proposal to me for a roof placement that included replacing rotten plywood with 1 2 cdx. He said it s only a difference of 1 8 thickness. Steeper rather than flatter roofs will have lesser load per sq. This kind of plywood can be used on roofs with minimal load.

A roof that lays practically flat will have a much heavier load than a steeper roof that allows rain snow and ice to roll right off. If you have any. Required dimensions of plywood for roofing. Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame.

That will suffice on a roof with rafters set 16 inches apart with minimal roof loads. Rafters that are slightly farther apart might require inch or 5 8 inch thick plywood. 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. Sheet with varying thickness.

In roofing plywood can be used as roof decking. The typical thickness range for sheathing is 3 8 to 3 4 inch. This minimum will only work if the rafters are set 16 inches apart at most and if the roof doesn t have too much load. I thought perhaps he made a mistake but no this is what he is proposing.

When used for roofing plywood panels are covered and protected by a variety of building materials that keep the elements at bay including roof felt underlayment flashing and shingles. Plywood typically comes in 4 8 ft. The minimum thickness of plywood used for roofing is 3 8 th of an inch. Never attach roof sheathing with staples.

The existing plywood on my roof is only 3 8. Sheathing should be a minimum of 19 32 inch thick. Loads will vary with the pitch of the roof. Most roofs will be sheathed in plywood at least 3 8 inch thick.

8d ring shank nails should be used instead. The most common thickness of plywood is 1 2 inch but plywood thickness can range from 1 8 inch to 3 4 inches. Roof decking is the material that lies on top of the main roofing structure and the underlayment and roof covering is applied on top. Unlike with plywood siding the plywood sheet to be used for sheathing should be at least 3 8 inch thick.