Modified Bitumen was first developed and utilized in Europe in the 1960s. This membrane is manufactured in uniform sheets comprised primarily of polymer-modified bitumen reinforced with one or more plies of fabric, or ply sheets. The fabrication can include polyester, glass, or a combination of the two. When applied in roofing, the finished version may be comprised of several sheets of modified bitumen and asphalt to create a uniform matrix.
When used in conjunction with a thermoplastic polymer, APP (Atactic Polypropylene), a uniform matrix is created within the modified bitumen sheets. This matrix increases the bitumen’s resistance to ultraviolet (UV) light, increases its flexibility in extreme temperatures, and increases it resistance to water penetration. This added resilience and enhanced durability under extreme conditions makes modified bitumen a prime choice when there may be movement or deflection of the underlying deck of a roof.
Modified Bitumen roofing systems create watertight barriers that perform for many years at a time due to the multiple layers. When built-up, these layers of bitumen exhibit exceptional resistance to conductivity of heat between the exterior and interior of the building. This generates noticeable reduction in heating and cooling costs. The thermoplastic polymers used in the modified bitumen make it more fire resistant as well. The technology employed in creating this roofing system makes it affordable and easy to generate as well.