Purpose Of Gravel On Gravel Roof

Most houses with flat or nearly flat roofs are topped with built up roofing or tar and gravel roofing made from fiberglass based asphalt sheeting that is applied in layers with hot bitumen tar mopped on between.

Purpose of gravel on gravel roof.

A tar and gravel roof is very heavy. First it is meant to protect the underlying layer of the materials used for built up roofs bur. Gravel provides shade to the top layer of asphalt tar protecting it from the ultraviolet rays in sunlight. Our experience is that most gravel roofs are 3 ply hot mopped asphalt built up with a gravel finish applied.

Generally the weight for a gravel coated roof must be within 10 25 pounds per square foot. One solution to this is a built up or tar and gravel roof where many layers of hot asphalt or bitumen tar paper and a waterproof membrane are applied and then covered with gravel. Too much gravel can result in a structural issue due to weight. Pea gravel crushed rock and decorative rock white quartz are often dispersed into a flood coat of hot asphalt and applied over the top of the roof membrane.

Therefore you can save money in the long run. Second contractors place gravel on single ply roofs to allow the roofing materials to remain weighed down and secure. Finding a leak in a sea of gravel can be very difficult even more difficult if the gravel has been set in a layer of hot asphalt. Aside from its low installation costs the roofing material does not require frequent repairs or replacement.

What is the purpose of the gravel on a flat tar roof. Contractors place gravel on roofs for two major reasons. Built up roofs or burs also called a tar and gravel roof is a well established and popular style of flat roof that is made up of alternating layers of roofing felt or fiberglass and asphalt that is applied with heat which combine to make a long lasting sturdy roofing system. Tar and gravel flat roofs are one of the most cost effective roofing solutions.

Disadvantages of a tar and gravel roof. A flat or low slope roof is often not a suitable surface for shingles or other roofing materials because moisture can t flow off them. A tar and gravel roof has a life expectancy of about 20 to 25 years. Friday july 6 2018.

There are different types and weights of gravel used on flat roofs for these purposes. Gravel to protect built up. A tar and gravel roof will generally last around 20 years although if they are well maintained and properly installed this kind of roofing has been known to last almost 40 years. This is called built up roofing.

Gravel is used on flat roofs for two reasons. To protect the underlying layer of roofing materials as is the case with built up roofs burs. To weigh down or secure the roofing material as is the case with single ply flat roofs.