Flat Roof Plywood Thickness

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.

Flat roof plywood thickness.

That s considered to be the minimum. He said it s only a difference of 1 8 thickness. I thought perhaps he made a mistake but no this is what he is proposing. In roofing plywood can be used as roof decking.

The minimum thickness of plywood used for roofing is 3 8 th of an inch. If you have any. Unlike with plywood siding the plywood sheet to be used for sheathing should be at least 3 8 inch thick. Roof decking is the material that lies on top of the main roofing structure and the underlayment and roof covering is applied on top.

This kind of plywood can be used on roofs with minimal load. Loads will vary with the pitch of the roof. The most common thickness of plywood is 1 2 inch but plywood thickness can range from 1 8 inch to 3 4 inches. 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.

8d ring shank nails should be used instead. Plywood typically comes in 4 8 ft. Foot and with a maximum of spacing of. 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.

Most roofs will be sheathed in plywood at least 3 8 inch thick. A local roofer submitted a proposal to me for a roof placement that included replacing rotten plywood with 1 2 cdx. Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame. 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. Sheathing should be a minimum of 19 32 inch thick. Steeper rather than flatter roofs will have lesser load per sq. Never attach roof sheathing with staples.

The typical thickness range for sheathing is 3 8 to 3 4 inch. Rafters that are slightly farther apart might require inch or 5 8 inch thick plywood. Sheet with varying thickness. The existing plywood on my roof is only 3 8.