PVC roofing (also called vinyl roofing) is used on roofs that are flat or have a very low slope. This roofing system comes as a single-ply sheet that has two layers of PVC with a layer of scrim in the middle. The difference between a PVC roof and a PVC pipe is that chemicals to protect from UV exposure and plasticizers (for flexibility) are added to the roofing membrane. The plasticizers added make the membrane extremely flexible giving it a skin-like feeling, and the layer of scrim gives the membrane its strength. One disadvantage PVC has is that the membrane’s curing process takes place over time on the roof and never fully cures. Because of this, it will eventually lose some of its elasticity and become brittle. However, a quality PVC roof should perform well for at least 25 years.
One of the biggest advantages of PVC is that it is rated as a Cool Roof by ENERGY STAR and offers up to 10% energy savings. (It is always best to have it power washed every year or two to keep up this energy efficiency). Some other benefits are that it is able to withstand ponding water without being damaged, and it is not harmed by large and rapid temperature changes (thermal shock) due to its ability to expand and contract. PVC also has the quality of being fire-retardant, and high-quality vinyl roofing actually self-extinguishes when the heat source is removed.