Goose Creek Roofing: Article About What's Under A Roof?
Most homeowners don't have any idea what is under the top surface of the roof that covers their home. Roofing is more complicated than its outer covering of asphalt, wood or tile. Besides the covering, the roof system is composed of an underlayment, deck, flashing and gutters. With an annual inspection, homeowners can rely on Goose Creek roofing professionals to keep all parts of a roof functioning properly.
The layer immediately beneath the roofing shingles is called the underlayment. This is the surface on which the shakes or shingles are attached. The most common type is roofing felt, more commonly known as tar paper. It is not actually made of paper but often consists of fiberglass that is impregnated with asphalt. Two basic thicknesses are available: 15 and 30 pound. The thicker, 30 pound material is somewhat more durable. Today's building codes require this material to be fire, wind and tear resistant. Its purpose is to provide added protection against moisture. In order to accomplish this, the layers must be overlapped slightly during installation. Also during installation, roofing felt often requires measures to keep it smooth in order to avoid wrinkling of the outer surface.
A roofing contractor from Lowcountry roofing of Goose Creek SC can answer any question about gutters or new roofs.
The advantage of roofing felt over other materials is the cost. While it is significantly less expensive than other types of material from which individuals can choose, it is not as durable.
Thermoplastic polyolefin (TPO) is a popular alternative to traditional tar paper. While it is more expensive, it does offer performance advantages. Instead of moisture being trapped underneath the surface, TPO allows the roof to breathe so that trapped moisture can escape. This helps to prevent the growth of mold. As opposed to roofing felt, this material is more durable, less susceptible to wrinkling and requires less overlapping at the seams because it comes in wider widths.
Beneath the underlayment is a layer of sheathing that attaches directly to the rafters. The most commonly used materials are plywood, particle board and wafer board. They are the least expensive and easiest to install of all the readily available materials in today's market. Sheathing, sometimes called decking, is the first solid surface above the rafters and, as a result, becomes a type of foundation that supports the main part of the roof. The standard size for a sheet of sheathing material is 4 feet wide by 8 feet long. The thickness can vary due to differences in local codes.