An Overview of Commonly Used Flat Roof Materials

Posted: Feb 13, 2013
Author: Race City Roofing

A flat roof enables you to maximize useable space above and below the roof. A flat roof is also a stylish and modern addition to any building. It’s important to know that this type of roof is not 100 percent flat. To prevent water from pooling and ultimately invading the interior, flat roofs are built on a slight incline – a minimum of ? of an inch per foot.

Since flat roofs don’t have big slopes, rainwater doesn’t run down them automatically. Therefore it’s absolutely essential to choose the correct roofing system for your specific design. Below are the most common materials:

SINGLE-PLY SYSTEMS

• TPO (Thermoplastic polyolefin) represents the fastest growing sector in the flat roof industry. This growth is being fueled by the demand for cool roofs, energy efficiency and reflectivity. TPO membranes are certified by the CRRC (Cool Roof Rating Council) and rated by Energy Star because they have had a direct impact on the reduction of cooling costs and energy consumption. TPO also provides high resistance to rooftop chemicals – including greases, oils and acids.
• PVC (polyvinyl chloride) is a flat roof membrane that has performed admirably for decades. It is also CRRC-certified and Energy Star-rated.
• EPDM (ethylene propylene diene terpolymer) has a 45-year history of proven performance. It has outstanding weathering characteristics and is low maintenance.

BUR (BUILT-UP ROOF) SYSTEMS

• These roofing assemblies comprise of alternating layers of asphalt and asphalt-coated reinforced sheeting. The level of reflectivity depends on the surface layer and color.
• A modified bitumen flat roof system is a hybrid. It has the benefits of a BUR, along with extra flexibility, strength and UV resistance.