Why Do They Have Gravel On Flat Roofs

These materials provide the waterproof barrier that contains and sheds the water to protect the roof structure.

Why do they have gravel on flat roofs.

Built up roofing bur was the most common type of flat roof before modified bitumen and membrane roofing were developed. Disadvantages of a tar and gravel roof. Pros and cons for flat roof materials. Gravel to protect built up.

To protect the underlying layer of roofing materials as is the case with built up roofs burs. I agree with steve c i do have worked with a contractor that does hot and shingle roofing and the gravel has it s purpose there. A flat roof should really have a minimum incline of 1 in 40 and preferably more otherwise rainwater will hang around long enough to support vegetative growth and long term settlement of. They tend to have a lifespan of around 20 to 25 years depending the location and the structure of the rest of the property barring any major natural disasters of course.

A tar and gravel roof is very heavy. Gravel is used on flat roofs for two reasons. A flat roof typically has a rubber or asphalt impregnated membrane. However both rubber and asphalt will lose plasticizers and other v.

Bur consists of many layers. There are different types and weights of gravel used on flat roofs for these purposes. Joists or the supports for your roof may have to be strengthened before application. A bottom layer or two of insulation board multiple intermediate layers of tar or asphalt alternated with layers of roofing felt and a top layer of gravel.

The benefits of a tar and gravel roof are numerous. 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. 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. 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.

A flat roof is a roof which is almost level in contrast to the many types of sloped roofs the slope of a roof is properly known as its pitch and flat roofs have up to approximately 10. Why install a tar gravel roofing system.