Purpose Of Gravel On Roof

Have you ever wondered why contractors install gravel on flat roofs.

Purpose of gravel on roof.

Also a tar and gravel roof is very rugged and safe to walk on. 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. Parts and composition of tar and gravel built up and flat roofing systems with a helpful tar and gravel roof construction diagram. A tar and gravel roof is very heavy.

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. Flat or almost flat roofs can collect a tremendous amount of water especially if their outlets or downspouts become plugged with leaves and debris. On many flat roof low slope commercial buildings it s common to see gravel on top of the roof. 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.

Disadvantages of a tar and gravel roof. 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.