Flat Roof Plywood Sheathing

A strong resilient roof is a home s first line of defense when the roof deck is exposed to weather.

Flat roof plywood sheathing.

It should be placed up on the roof. Zip system roof assembly combines our revolutionary integrated sheathing and flashing tape or liquid flashing to provide a sealed roof for protection against moisture intrusion during construction or if high winds strip the roof covering away. One of the nice things about plywood is the variety of options you can buy. 8d ring shank nails should be used instead.

Before lumber companies began selling osb the standard choice for sheathing a roof with a 24 inch rafter spacing was 1 2 inch cdx plywood the letters cdx indicate that it is construction grade. That s considered to be the minimum. Plywood is a bit more expensive but is usually stronger and is often selected in cases where the roof covering is heavier such as for slate clay or concrete tile roofs. Unlike with plywood siding the plywood sheet to be used for sheathing should be at least 3 8 inch thick.

The common grade of plywood for roof sheathing is cdx. So dividing the area of the roof by 32 will give you the number of. Odds are that if you pass a housing development of wood framed houses it will have osb oriented strand board as exterior sheathing. A 4 8 sheet of plywood is 32 ft 2.

One side is usually better quality than the other c in this case. If your roof has triangles and other shapes you ll need to use a calculator to find the square footage. Installing sheathing on a flat roof is much easier than working on a peaked roof. Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame.

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. When you count sub floors roofs and wall sheathing osb claims about 70 of the wood sheathing market in north america over plywood. A is smooth and knot free while d the lowest quality has missing knots and cracks. Never attach roof sheathing with staples.

The typical thickness range for sheathing is 3 8 to 3 4 inch. That s considered to be the minimum. Plywood is made with an odd number of layers for optimal strength and performance. As a quick primer in plywood each side is rated from a to d.

Sheathing should be a minimum of 19 32 inch thick. Follow these 5 simple construction steps for roof sheathing. Plywood is typically.