Why Do You Put Gravel On Flat Roofs

The layer of gravel on a low slope flat roof is used to help keep the underlay fabric secured and to provide some protection from the elements and human interference.

Why do you put gravel on flat roofs.

The first is to protect the underlying layer of roofing materials on built up roofs burs and the second is to secure or weigh down the roofing material as is the case with single ply flat roofs. In a typical tar and gravel roof which by the way is gradually being supplanted by gravelless roof systems you put down a layer of tar paper then tar and finally gravel. Because the gravel holds and releases heat the layer of gravel on a bur flat roof can both help water evaporate and. In most cases a torch that is heated to over 2000 degrees is required.

They provide a loading coat and they afford uv protection. Contractors and builders use gravel on flat roofing for two primary reasons. The weight provided by the gravel is used to anchor down the roof materials therefore using far fewer fasteners to hold the materials to the decking. Adding a pitch to a flat roof requires construction.

Putting a thin layer of gravel usually river gravel for the smooth. Gravel and pea shingle have two primary purposes on a flat roof. Gravel is an excellent fire retardant. This roof type is typically composed of overlapping layers of tar paper or rubber sheeting separated by tar.

Talk to ten roofing contractors and you ll get ten answers on what the gravel is for but this seems to be the consensus. You may notice that a tar and gravel roof is installed on many low slope or flat roof commercial buildings. A flat roof can remain leak free for around 7 years. Specifically there are two main reasons to use a ballasted roof system.

On top of that many roofers prefer to use a roll out roofing system. As ballast the gravel will help anchor the material underneath and lower the risk of it being blown off in high winds. Of all the flat roofing options a tar and gravel roof is the most economical. Also a tar and gravel roof is very rugged and safe to walk on.

This poses many risks. It provides excellent protection against uv rays and is an attractive option for windows and decks that overlook the roof. The gravel also acts as a protective measure to prevent natural debris such as leaves. Tar has a low melting point.