TPO membranes are single-ply roof membranes constructed from ethylene propylene rubber. They are designed to combine the durability of EPDM rubber with the proven performance of hot-air weldable seams. They have been tested as having excellent resistance to ozone, are algae-resistant, environmentally friendly and safe to install. TPO is highly resistant to tears, impacts, and punctures with good flexibility to allow for building movement. TPO's are available in white, light gray, and black.

Properly installed TPO roof systems have service lives ranging from about 10 to 20 years, depending on the type of installation. Full removal of the existing roof, the amount of slope the roof has, weather conditions, as well as several other criteria contribute to the longevity of a roof's service life. Typically, if you remove an old roof down to the deck before installing a new one, then the new roof will last longer. Also, the steeper the slope and the less severe the weather conditions, the longer a roof will last. High winds and hail can do a roof in rather quickly.