EPDM
Ethylene propylene diene monomer rubber
EPDM Is a synthetic rubber most commonly used in single-ply roofing because it is readily available and simple to apply. Seaming and detailing has evolved over the years and is fast, simple and reliable with many membranes including factory applied tape, resulting in a faster installation. The addition of these tapes has reduced labour by as much as 75%.
​
It is a low-cost membrane, but when properly applied in appropriate places, its warranted life-span has reached 30 years and its expected lifespan has reached 50 years.
​
There are three installation methods: ballasted, mechanically attached, and fully adhered. Ballasted roofs are held in place by large round stones or slabs. Mechanically attached roof membranes are held in place with nails and are suitable in some applications where wind velocities are not usually high. A drawback is that the nails penetrate the waterproof membrane; if correctly fastened the membrane is "self-gasketing" and will not leak. Fully adhered installation methods prove to give the longest performance of the three methods.
​
The most advanced EPDM has been combined with a polyester fleece backing and fabricated with a patented hot-melt adhesive technology which provides consistent bond strength between the fleece backing and the membrane. This has resulted in largely eliminating shrinkage of the product, whilst still allowing it to stretch up to 300% and move with the building through the seasons. The fleece improves puncture and tear resistance considerably; 45-mil (1.1 mm) EPDM with a fleece backing is 180% stronger than 60-mil (1.5 mm) bare EPDM. Fleece backed EPDM has a tear strength of 39.9 kN/m (228 lbf/in) compared to 13.1 kN/m (75 lbf/in) of that without the fleece reinforcement, more than 3 times the strength of non-reinforced membranes.
This thermoset polymer is known for long-term weathering ability and can withstand fluctuations in temperature and ultraviolet rays. They can also be great energy savers.
​
Source: Wikipedia
