EPDM (Ethylene Propylene Diene Monomer) is another waterproof membrane used on flat roofs. The principle components are ethylene and propylene with diene added to create a flexible, rubber covering. EPDM has been used in Canada since the 1960s as well, but many professionals believe it is the environmentally beneficial alternative to MB roofs. EPDM membranes are one ply systems, with an average thickness of 45 millimeters, about the thickness of a dime, 60 or 90 millimeters. The EPDM sheets are 50 to 100 feet long which means seams are unnecessary for most home applications. Because EPDM is flexible and sold in longer sheets, it can be easily manipulated to fit irregularly shaped roofs. The benefits of using EPDM membranes for flat roofs include resistance to weather fatigue caused by hail, extreme heat, and ozone or Ultraviolent radiation, and it remains flexible in low temperatures reducing cracks or ‘alligators’ in the membrane. For home owners who wish to use the runoff water from their roofs for sanitation or gardening purposes, the EPDM is the best installation choice because it does not pollute water with volatile organic chemicals found in other roof membranes. For more information on flat roof membranes, it’s best to contact a trusted roofing professional. The life span of any flat roof depends on weather and wear, but more importantly, the installation – proper installation means a long-lasting and low-maintenance roof over your head.