modified bitumen

Trusted Protection

Introduced in the 1970s, modified bitumen features asphalt that has been modified (thus called modified bitumen). It features two plies of roofing membrane and modified asphalt creating a strong, reliable roofing system. Modified Bitumen roof systems have the widest range of application methods as they can be hot-mopped, cold-applied, heat-welded, or self-adhered. First, one ply of smooth-surfaced base sheet is installed, usually over insulation and cover board. Then the system is finished with a granulated cap sheet applied over the smooth base/ply sheet. With multiple layers of protection and many application methods, it is still one of the most trusted low slope roofing systems used in the industry today.

All Modified Bitumen membranes are classified by ASTM numbers, types, and grades.

Attributes of a Modified Bitumen Roofing System


Like any roofing system, maintenance is key. These systems are known to perform well past the warranty term if maintained properly.

UV REsistance

Different surfacing options are available including “cool roofing” options that can help reduce your energy bill and extend the life of your Modified Bitumen roof.

weathering Resistance

Modified Bitumen roof systems perform very well in many different types of environments and weather-related exposures.

fire resistance 

Like other roofing systems, when installed over a specific deck and insulation, Class A fire ratings can be achieved.


Long-term warranties are available to meet your specific needs.

chemical resistance

This roofing system does not perform as well as others on the market when it comes to chemical resistance