If you have a home with a flat roof a tar and gravel roof may be a good option for you.
Gravel roof weight.
To protect the underlying layer of roofing materials as is the case with built up roofs burs.
The last things to assess are the estimated weight of the required gravel and its cost.
The buildup is ballasted with a gravel layer of at least 50 mm and 80 kg m 2.
When calculating the gravel weight make sure you do not confuse the tonne metric ton with the ton short ton.
Gravel roof advantages most gravel roofs are inexpensive to build offer some protection to vulnerable asphalt against uv damage and the stones are very durable.
Gravel roof disadvantages on the other hand gravel roofs are hot energy inefficient heavy moisture trapping and unstable.
Too much gravel can result in a structural issue due to weight.
To weigh down or secure the roofing material as is the case with single ply flat roofs.
Generally the weight for a gravel coated roof must be within 10 25 pounds per square foot.
Finding a leak in a sea of gravel can be very difficult even more difficult if the gravel has been set in a layer of hot asphalt.
The first one is used by all countries in the world and is defined to be equal to 1000 kg by the international body of standardization.
Gravel to protect built up.
You can calculate the required volume of gravel by multiplying the gravel path area by the desired thickness.
Contractors and builders use gravel on flat roofing for two primary reasons.
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.
Tar and gravel roofing.
A built up roof for example will typically include the built up membrane itself with or without gravel as well as some kind of insulation and cover board which will vary in thickness from roof to roof.
The weight of roofing constructions above the truss rafter may be estimated with the calculator below.
When it comes to estimating the weight of an existing roof field verification of the in place construction is necessary.
The single ply membrane and other roof components including thermal insulation are loose laid.
There are different types and weights of gravel used on flat roofs for these purposes.
Gravel is used on flat roofs for two reasons.
None asphalt roll roofing.
Felt tar and gravel roofing 3 ply 4 8 lb m ft 2 23 4 kg m 2 felt tar and gravel roofing 4 ply 5 3 lb m ft 2 25 9 kg m 2.
Gravel ballasted roofs with sikaplan or sarnafil single ply membranes are conventionally installed.
The ton is currently only used in the united states and is equal to 2000 pounds 2000 lbs.