On most flat roofs such as epdm tpo or modified it is perfectly acceptable to two layers of roofing.
Flat roofing layers.
Bur consists of many layers.
Bur systems are redundant meaning if one layer breaks down multiple remaining layers provide immediate protection.
Modified bitumen cap sheet roofing was developed in the 1960s as a replacement technology for bur or built up roofing by using the proven technology of bur but also adding polymer reinforced roof wear layers or cap sheets.
The number of plies on a roof implies the number of layers i e.
If the roof seems to be good and solid throughout its base and layers there is no need for a replacement and an layer of epdm tpo or asphalt roofing should be strongly considered in order to maximize the stability of the roof.
Adhesive metal straps or gravel are used to secure the rubber roof systems.
Pvc single ply membrane arguably the most popular of all flat roofing materials some contractors even install only pvc membranes for higher end residential installations pvc membranes are a single layer of thermoplastic material.
For many years it was acceptable to put even the third layer.
Flat roofs are an ancient form mostly used in arid climates and allow the roof space to be used as a living space or a living roof flat roofs or low slope roofs are also commonly found on commercial.
Steep sloped roof products such as tile slate metal and shakes only allow one layer.
Pvc roofs are especially strong and durable featuring a minimum breaking point of 300 pounds per inch.
Rubber is waterproof and is relatively easy to install.
Four plies denotes a four layer flat roof membrane system.
Built up roofing bur was the most common type of flat roof before modified bitumen and membrane roofing were developed.
Flat roofs are hard to replace.
Overall the amount of layers that can be added to flat roofs depends on the initial layer of roofing.
Drawbacks include potential leakage at the seams or from product shrinkage.
These systems also offer great tolerance for building stress and resistance to thermal shock.
Some observers suggest it s harder to replace a flat roof than a traditional pitched shingle roof because of the labor required to remove its layers especially on older flat roofs.
Always stand on a firm section of the roof and wear long pants long sleeves and safety glasses.
But now flat roofs often are constructed with fewer layers because of improved waterproofing technology.
On the plus side.
This could mean flat roofs may not raise the same red flags they used to.
These flat roof systems contain one layer of rubber or a rubber type material that is applied without heat.
Plies are the layers of felts fabrics and mats that make up roofs.
Remove the plies of the flat roof by thrusting into them with a spade.