They are composed of layers of perforated felt or fiberglass material with asphalt in between flooding the top with asphalt and applying gravel to the hot asphalt.
Flat roof gravel repair.
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.
Of course flat roofs are not flat but have a very slight roof pitch of between 1 4 to 1 2 per foot.
Concerns about flat roof repair vs replace.
To weigh down or secure the roofing material as is the case with single ply flat roofs.
Getting a new roof installed is a major investment especially in the case of tar and gravel flat roofing systems which many require significant maintenance or tar roof repair over the course of their existence which can extend for several decades.
Just enough slope to drain water but also flat enough to be a problem if not constructed properly.
Tar gravel roofs have been around for centuries.
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.
Flat roofs which are mostly level are common on older homes and in arid environments.
Tar and gravel roofs consist of layers of tar and roofing felt.
Gravel to protect built up.
Most flat roofs are made of asphalt rubber.
Understanding the basics of a tar and gravel roof also known as a hot mop roof is important when checking for leaks.
These roofs work well but you do need to inspect them on occasion for cracks and other signs of damage.
There are different types and weights of gravel used on flat roofs for these purposes.