For the chemically-minded readers, EPDM consists mostly of ethylene, propylene, and diene, hence the name. The actual chemical mixtures vary, but ethylene is the main ingredient with at least half the compound being made with it.

With a combination of these chemicals, EPDM comes out with the flexibility and durability that gives it superior resistance to cracking under sun exposure for long periods of time.

While it can work well alone, it’s been proven effective to pair EPDM with some form of insulation underlayment but you don’t have to. Sheets of EPDM are laid out over the entire area of your roof and sealed together with specialized tape that took decades to invent.

No welding is necessary, so it can be installed or repaired easily and quickly in many types of weather. The elastic material boasts unprecedented impact resistance among single-ply membranes, which are roofing materials done with one layer.

Again, though, improvements have been made that offer even thicker layers of EPDM to be chosen if you plan for a lot of foot traffic or hail. The thicker material also withstands punctures and tears better, so it’s worth the investment if you need it.

One area that EPDM shines is how well it holds up against sunlight and UV rays, because the black material absorbs the rays without cracking or aging. It’s important to know that EPDM is available in white to reflect UV rays if you’re in a warmer climate.