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.
Gravel flat roofs.
There are different types and weights of gravel used on flat roofs for these purposes.
Of all the flat roofing options a tar and gravel roof is the most economical.
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.
Our roof gravel is available for delivery in tunnel lift bulk bags allowing an easy method of transporting the gravel onto a roof using a crane not provided.
Built up flat roof replacement.
A built up flat roof bur is made up of tar and gravel.
Gravel roof disadvantages on the other hand gravel roofs are hot energy inefficient heavy moisture trapping and unstable.
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.
Roof gravel provides a protective layer to flat roofs reducing the weather damaging effects from uv rays and heavy snow hail and wind.
Built up roofs or burs also called a tar and gravel roof is a well established and popular style of flat roof that is made up of alternating layers of roofing felt or fiberglass and asphalt that is applied with heat which combine to make a long lasting sturdy roofing system.
Also a tar and gravel roof is very rugged and safe to walk on.
Of course flat roofs are not flat but have a very slight roof pitch of between 1 4 to 1 2 per foot.
Gravel to protect built up.
It provides excellent protection against uv rays and is an attractive option for windows and decks that overlook the roof.
Gravel is an excellent fire retardant.
However if epdm roofs are spray applied then the chance of the seams pulling away from the roof is significantly lowered.
Just enough slope to drain water but also flat enough to be a problem if not constructed properly.
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.
Built up roofing bur was the most common type of flat roof before modified bitumen and membrane roofing were developed.
It also provides protection from foot traffic.
To weigh down or secure the roofing material as is the case with single ply flat roofs.