Rockland County Roofing: Article About Roofing Felt
Rockland County roofing professionals use roofing felt as an underlayment on the roof before asphalt or wood shingles are applied. Roofing felt looks a lot like black tar paper. The primary purpose of this underlayment is to prevent water from leaking into the roof decking and eventually into the home. Roofing felt is sold in rolls and is made from fiberglass or polyester that has been saturated with asphalt. Some felt paper is sprinkled with sand.
Roofing felt is so thin that its thickness is not measured in depth, but instead like paper, it is measured in pounds per square. Each square of roofing felt is approximately 100 feet of roofing material. The two most common roofing felts are #15 and #30. This felt paper weighs 8 and 20 pounds per square feet respectively. Rolls of felt will be cut to match the length of the roof.
Both building codes and insurance companies require that a minimum of #15 felt or heavier is used in all roofing installations. In addition to preventing water filtration, roofing felt is fire retardant. It also protects the shingles by preventing any sap or resin that seeps out of the wood deck from damaging the shingles.
The roofing experts at Precision roofing of Rockland County can answer questions regarding TPO roofing or PVC roofing.
Roofing felt gives the roof a smooth appearance, and it prevents the slight changes in height of the roof sheathing from being reflected in the asphalt shingles.
The Asphalt Roofing Manufacturers Association stipulates the amount of felt that should be applied depending on the slope of the roof. For example, a roof that has a slope that is between 3:12 and 4:12 would need two layers of #15 felt before asphalt shingles would be installed. A roof that has a slope in excess of 4:12 has better drainage from the roof. For this reason, roofers will just use one layer of #15 felt. If the weight of the shingles is more than 240 pounds per square, then it is recommended that installers use #30 felt paper.
Installers must follow the guidelines laid out by the roofing felt manufacturer since each manufacturer has different standards for installation. Special attention should be paid to areas that have the most water runoff, including ridges and roof hips as well as areas around walls and around chimneys that are not on the peak of the home. These areas should be covered with additional felt in each direction.
Roofing felt serves a vital role in helping homeowners maintain their roof and prevent leaks. It is vital that contractors pay close attention to how they install this material if they want to maximize the roof's lifespan.