Why Do People Put River Rocks On Flat Roofs

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.

Why do people put river rocks on flat roofs. All three types of flat roofing cost 250 to 350 per square 100 square feet but prices vary according to region and size of the roof. Epdm and neoprene roof seams are fastened by adhesive and pvc roof seams are heat or solvent welded. The membrane is. If there is a complete covering of the roof with small rocks gravel then it is the top layer of a built up flat roof.

All the suspect areas have a third layer of felt also. The extension is directly beneath the back windows so looks un sightly. This protects the other layers from damage by hail or storms also people walking on the roof so they do not damage the waterproof layers below. It has a layer of undercoat and then a layer of the self adhensive felt on the top.

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. It has a very low slope between 1 4 to 1 2 inch per foot so that it drains water. 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. Gravel is used on flat roofs for two reasons.

Membrane roofs are attached in a variety of ways. I have just had a flat roof put in on an extension. To weigh down or secure the. But such a low slope holds snow and water much longer than a steeply pitched roof and therefore needs a very different material to stay watertight.

Both factors can extend the life of your flat roof. Have you ever wondered why contractors install gravel on flat roofs. Tar has a low melting point. Specifically there are two main reasons to use a ballasted roof system.

Flat roofing is not actually flat. They can be partially loose laid and held down with river rock ballast requires roof structure to support the weight or fully adhered to the roof deck. To protect the underlying layer of roofing materials as is the case with built up roofs burs. Rocks are placed on commercial flat roofs for many different reasons if the roof is what is called a ballast roof it is not fastened or adhered down throughout the whole roof.

Talk to ten roofing contractors and you ll get ten answers on what the gravel is for but this seems to be the consensus.