A protected membrane or PMR roof (sometimes called an inverted or upside down roof) uses the same materials as a conventional roof but places insulation on the top of the membrane. Insulation boards are loose-laid over the membrane and then weighted down with gravel ballast, paving slabs, or soil in the case of “green” or vegetative roofs.
Invented in the late 1960’s, a protected membrane roof system uses DuPont™ Styrofoam™ Brand XPS Insulation to protect the membrane, helping improve the performance and longevity of the entire roof system.
Protected membrane roofs are becoming a popular alternative to conventional roofs because they are cost-efficient and energy-saving, improve occupant satisfaction, provide long-term performance and sustainability benefits, and increase community resilience.
A protected membrane roof system works because DuPont™ Styrofoam™ Brand XPS insulation is inherently resistant to moisture and durable enough to withstand prolonged exposure to the environment.
Explore products for protected membrane roofs.
Ballast roofs are your typical protected membrane roof design. Rather than soil and vegetation or pavers, they use stone or gravel to hold the roofing components in place. A ballasted roof is durable, energy efficient, economical, and fast and easy to install.
A green roof, also known as a vegetative or garden roof, is a protected membrane roof design that uses soil and vegetation to hold the roofing components in place. A green roof can lower cooling costs, reduce storm water runoff, promote biodiversity and improve air quality.
A blue roof is a protected membrane roof design that helps manage storm water. It promotes lateral drainage, captures water for irrigation, and blends well with green roof assemblies.
Paver protected membrane roofs are durable and energy efficient. They add valuable rooftop recreation space. Additionally, paver PMR assemblies blend well with green and blue roof assemblies.
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