On most flat roofs such as epdm tpo or modified it is perfectly acceptable to two layers of roofing.
Flat roofing layers.
Built up roofing bur was the most common type of flat roof before modified bitumen and membrane roofing were developed.
Always stand on a firm section of the roof and wear long pants long sleeves and safety glasses.
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.
This could mean flat roofs may not raise the same red flags they used to.
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.
Remove the plies of the flat roof by thrusting into them with a spade.
But now flat roofs often are constructed with fewer layers because of improved waterproofing technology.
Bur consists of many layers.
Four plies denotes a four layer flat roof membrane system.
Rubber is waterproof and is relatively easy to install.
Flat roofs are hard to replace.
Asphalt shingles typically can have one more layer added over the top two roofs total.
These flat roof systems contain one layer of rubber or a rubber type material that is applied without heat.
For many years it was acceptable to put even the third layer.
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.
Steep sloped roof products such as tile slate metal and shakes only allow one layer.
Overall the amount of layers that can be added to flat roofs depends on the initial layer of roofing.
On the plus side.
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.
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.
Bur systems are redundant meaning if one layer breaks down multiple remaining layers provide immediate protection.
Plies are the layers of felts fabrics and mats that make up roofs.
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.
Adhesive metal straps or gravel are used to secure the rubber roof systems.
Pvc roofs are especially strong and durable featuring a minimum breaking point of 300 pounds per inch.