EPDM (Ethylene Propylene Diene Monomer) rubber roofing is the most commonly used single-ply membrane for an elastomeric system. It can be installed in temperatures as low as 5F and has a long history of successful installations worldwide. The EPDM membrane is rated for many years, often with long warranties.
EPDM rubber roofing / EPDM membrane is a thermoset elastomeric membrane that is reinforced with 3/8 to 1-3/8 fibreglass mat or polyester fabric, depending on the manufacturer and product line. The membrane consists of an ethylene-propylene dior monomer base with other chemical additives added to control flexibility, ageing and temperature. The base is partially polymerized in large horizontal moulds called autoclaves. As the EPDM compound leaves an autoclave it goes through a cure cycle and eventually becomes a tough relatively rigid sheet of rubber-like material (with some flex).
EPDM has many advantages as a roofing material. It is highly resistant to the deleterious effects of ultraviolet radiation from sunlight, ozone and many weathering agents. EPDM also has a high resistance to heat (up to 350 degrees F), it will not burn nor support combustion.
However, there are also some downsides to EPDM rubber roofing.