Why Put Stones On Flat Roofs

There are different types and weights of gravel used on flat roofs for these purposes.

Why put stones on flat roofs.

The stones does 3 things 1 help to keep the roof fire resistance. A built up roof bur sometimes called a tar and gravel roof is a tried and true style of flat roof. The stones force it to stay put. For mineral based felting the pebbles are there to help protect the felting as ballast depending on the fitting type and to help prevent water pooling aparantly.

A layer of gravel or small stones is applied on top of the final coating of asphalt to protect the roof from the elements including. The gravel prevents sun hail errant baseballs etc from damaging the membrane the all important moisture seal created by the tar paper and tar. 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. Gravel to protect built up roofs.

Having a large flat roof this is something that i pondered on too. Both factors can extend the life of your flat roof. If the roof is a built up roof made with layers of tar and bitumenous sheets it creates a wear layer for the roof. On more expensive mebrane rooves you dont need pebbles.

What are tar gravel roofs or built up roofs. Specifically there are two main reasons to use a ballasted roof system. 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. The chips act as a barrier between non solar reflective felt and the sun basically help prolong its life span of the felt if its green mineral on your new roof you will not have to chip it as the minerals are solar reflective.

But as said the stones help the roof from bubbling etc from the sun. Your roofing merchants can supply the stones. 2 to break up the rain into fine mists and keep the noise level down. This is the protective cover that keeps the layers of tar and bitumen from deteriorating in the weather.

3 to protect the roofing felt from perishing and heat melting the bitumen. Here alternating layers of roofing felt usually fiberglass and hot applied asphalt are combined to create a long lasting roof system. There are several reasons flat roofs have stones. No stones for us as it was a bay window.

Stone is also used as a ballast for single ply membrane roofing. We had to replace a big portion of our flat roof recently. We used on a flat roof bitumen mastic to plug a hole we then painted with a water proof roofing paint. Built up roof bur the traditional hot tar and gravel.