Modified Bitumen Roofing System

spray foam re-roof

The fact that a modified bitumen roof is fully adhered to a structure, either using adhesive or torched with heat, is qualification to reroof that surface with a spray foam roofing system.  Even a modified bitumen roof with granules qualifies as the granules are fully integrated into the top layer.

What is Modified Bitumen Roofing?

Modified Bitumen (MB) roofing is an asphalt-based, close cousin of the Built-up-Roof (BUR) designed for buildings with low-slope or “flat” roof structures.  With five layers of protection, it’s one of the most trusted flat roofing systems used in the industry today.

Modified Bitumen was developed in Europe during the 1960s, and it is a rendition of the old built-up roofing (BUR) system. Modified Bitumen flat roofing is a single-ply system made of asphalt bitumen, modified with polymers, and reinforced with fiberglass and/or polyester.

It is assembled in a unique permutation of layers that compound to increase the roof’s effectiveness. It’s this permutation of materials that gives Modified Bitumen competitive advantages that few other roofing systems can match.


Modified Bitumen Pluses 

  1. Seamless Connections

There are three popular ways to install Modified Bitumen: self-adhesive, cold adhesive, and heat. All of them create a tight connection creating a consistent and seamless connection between the sheets.

  1. Leak Resistance

One of the top concerns associated with flat roofing systems is leakage. However, due to the coherent nature of this roof’s installation, leakage is not a problem.

  1. UV and Heat Resistance

Modified Bitumen is well known to be heat reflective. These reflective properties also make it resistant to the sun’s radiation. This can help to reduce energy costs, especially if lighter colors or more reflective top coatings are used.

  1. Tear Resistance 

Due to the combination of fiberglass and/or polyester reinforcement layers, these roofs are tear-resistant and can handle foot traffic well.


  1. Weather Resistance 

Modified Bitumen Roofing Systems are designed with a 5 layer composition to withstand harsh exposure to all seasons and other dangerous environmental elements.

  1. Style Options

You have multiple options for color with this roofing. The granules on the cap sheets can vary to match any color of shingles.

  1. Easy To Install and Repair

Modified Bitumen is easy to install. They come in rolled sheets that are 3 feet wide and up to 36 feet long, which are rolled easily onto the roof atop a base sheet membrane. If damaged, bitumen patches can be used to quickly and efficiently repair it.

  1. Environmentally Friendly

Some Modified Bitumen materials can be recycled. This means that your roofing materials can get reused and it can avoid getting added to the inevitable dump pile. This will help reduce your carbon footprint.

Reroofing with spray foam is also possible on these other commercial roofing system types.

Built Up Roofing Systems | EPDM | Metal Roofs | Modified Bitumen Roofing System | Single Ply | TPO