The latest numbers show new records for both plywood and OSB production. The combined total output for both materials in the first nine months of 2002 is 30.8 billion square feet.

Plywood used to be king for wall sheathing and flooring material, but oriented strand board (OSB), introduced in the late 70s, is now the most popular.

Years ago, when I was still a pup carpenter, plywood was the king of both wall sheathing and roof sheathing. OSB sheathing has now pushed plywood to the back buildings of the lumberyards.

The furring strips run vertically up the roof, not horizontally. New sheathing - sheets of either plywood or oriented strand board (OSB) - is then nailed to the furring strips.

A piece of one-half-inch plywood in my area that a builder would use on a roof or a sidewall costs about $2.60 more than a similar piece of OSB. A sheet of 3/4-inch sub-floor plywood costs $5.38 ...

Years ago, when I was still a pup carpenter, plywood was the king of both wall sheathing and roof sheathing. OSB sheathing has now pushed plywood to the back buildings of the lumberyards.

ROOF SHEATHING Copies of the National Association of Home Builders’ report on fire-retardant-treated plywood are available on request at telephone number (800) 368-5242.