Why Do You Put Gravel On Flat Roofs

The gravel covers a tar roof.

Why do you put gravel on flat roofs.

To weigh down or secure the roofing material as is the case with single ply flat roofs. They provide a loading coat and they afford uv protection. Most flat roofs traditionally have tar applied over the roof decking to make it watertight. A built up roof bur.

To protect the underlying layer of roofing materials as is the case with built up roofs burs. There are different types and weights of gravel used on flat roofs for these purposes. 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. Built up roof bur the traditional hot tar and gravel roof is built from three or more plies of waterproof material alternated with hot tar and ballasted by a layer of smooth river stone.

Flat roofs usually come with a 10 to 20 year warranty but can last 25 years if you build the roofs right and maintain them using commonsense rules. These roofs are installed as thin sheet materials 0 030 30 mils to 0 060 inches 60 mils thick and are applied to the roof in a single layer. Gravel to protect built up roofs. Walked on gravel tends not to hurt the seal of the tar underneath.

Gravel is heavy and concentrations of gravel can contribute to roof deck deflection low areas. Why do you put gravel on a flat roof. Contractors and builders use gravel on flat roofing for two primary reasons. Gravel is used on flat roofs for two reasons.

As ballast the gravel will help anchor the material underneath and lower the risk of it being blown off in high winds. Walking on the tar would hurt the tar s seal fast. So all you need to be able to say to your roof contractor is you want an epdm rubber roof. Gravel and pea shingle have two primary purposes on a flat roof.

First of all it weighs down the covering surface of the roof and secondly it protects the roof from sun damage.