Why Is There Gravel On Flat Roofs

The stones force it to stay put.

Why is there gravel on flat roofs.

Yet like all roofing styles flat roofs are subject to certain problems as time goes on. Once made of tar paper these types of roofs gradually are using more advanced materials such as fiberglass membranes. Flat roofs are a feature of many commercial buildings. By far the biggest advantage of using a flat roof is the expense.

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. Bur consists of many layers. From the initial building and installation to the materials most often used to cover the roof flat roofs are fairly cheap. There are different types and weights of gravel used on flat roofs for these purposes.

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. 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. To weigh down or secure the roofing material as is the case with single ply flat roofs.

The result is a thick tough seamless roof assembly that is highly resistant to damage. This roof type is typically composed of overlapping layers of tar paper or rubber sheeting separated by tar. Tar has a low melting point. They also make roof and building repairs a much less daunting task.

In the summer it gets pretty soft and if left to its own devices would flow to the lowest point on the roof. The gravel is mostly put on flat felt roofs to serve as a heat barrier from the sun otherwise the felt would soften and blister and then when it was cold the creases in it would crack and cause leaking put too much on and the weight of the gravel will crack the felt as well and cause an increase in weight on the flat roof and possibly buckle. 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. You may notice that a tar and gravel roof is installed on many low slope or flat roof commercial buildings.

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 roof leaks are among the most common and the most.