Roof sheathing is a layer of material that is installed between the frame of a roof and the roof coverings. When it is properly installed, it increases the rigidity of the roof frame by ensuring that the roof rafters or trusses remain properly spaced, and it creates a secure and level roof deck to serve as a base for the installation of roof coverings. The materials that are most commonly used by Bergen County roofing specialists are panels of plywood and oriented strand board, both of which are considered essential for a quality roof sheathing system.
The particular type of plywood used for roof sheathing is usually CDX plywood, a construction grade wood that is often used for exterior applications and that has been a long time standard sheathing choice. It is manufactured by having sheets of veneer stripped from lumber and laminated together so that the wood grain in each layer is nonparallel to the wood grain of adjacent layers. The resulting panels are very durable, water resistant and, if exposed to moisture, able to dry quickly. The plywood panels are sold with widths of four feet and maximum lengths that can range from 8 feet to 10 feet.
Oriented strand board, or OSB, is composed of compressed layers of rectangular wood filaments, wax and adhesives. It is densely packed and has none of the internal gaps that are sometimes present in plywood.
The expert roofers at All Professional Remodeling of Bergen County can assist you with any questions regarding roofing, skylights or gutters.
OSB is often favored since it can cost half of the price of plywood and can bear a heavier load due to the way it is manufactured. It is also sold as panels with widths of four feet, but with maximum lengths that are almost double those of plywood. The panels have a textured surface that reduces slippage and lines at 16 inch and 24 inch intervals that make it easy to target rafters and joists for nailing.
Both plywood and OSB panels are available in thicknesses that range from five sixteenths of an inch to three fourths of an inch. The thickness of the sheathing that will be used to build the roof deck is determined by many factors, some of which include the choice of roof covering, the spacing between the trusses or rafters of the roof frame, the roof design and local building codes.
While proper installation of roof sheathing is an important part of a working roofing system, the materials that are used are just as significant. The use of plywood or OSB for roof sheathing is the best way for a roofing contractor to ensure that a roof is able to maintain its structure and support the homeowner's choice of roof coverings.