Using Pressure Treated Plywood For Roof

Treatment chemicals include chromated copper arsenate cca ammoniacal copper quat acq copper azole ca and safest of all borates.

Using pressure treated plywood for roof.

Wood for any outdoor project should be pressure treated. Use pressure treated wood in any situation where there s direct contact between the wood and anything that could supply moisture. Pressure treated wood is required whenever you attach framing lumber or furring strips directly to concrete or other exterior masonry walls below grade. Wood for indoor projects should be left as is.

Note that this requirement is only for exterior walls as these may wick moisture onto the lumber. This means posts in contact or buried underground obviously but it also includes any lumber touching concrete or masonry since it s porous and wicks water like a sponge. Pressure treated wood already has a built in water resistance. Pressure treated plywood usually has a greenish hue and a slightly oily surface.

One of the nice things about plywood is the variety of options you can buy. If you are constructing a roof deck you will need to be concerned with the amount of water that gets on the wood. Interior walls are within a climate controlled environment and are presumed to be free of moisture. Where to use pressure treated wood.

It adds proven performance and durability to new homes room additions and renovations. Galvanic corrosion occurs when electrons move away from an anode toward a cathode. There are pressure treated grades marine grades that can be used in water fine hardwood options for finish work and cabinetry pre finished panels or simple down and dirty 1 2 cdx plywood. Most pressure treated wood is treated with chromated copper arsenate.

Plywood sheathing is ideal for residential and light plywood sheathing is ideal for residential and light construction and every piece meets the highest grading standards for strength and appearance. Pressure treated lumber is one of the best options that you can use for a roof deck because of its extreme durability. I would be concerned that galvanic corrosion could degrade the metal roofing or fasteners. The metal present in the treatment chemical copper is dissimilar to the metal roofing steel.

While many homeowners wonder if they should use pressure treated wood for a specific project the answer is simple. The sawdust from pressure treated wood is an irritant to the eyes skin and nose.