Modified materials have inherent characteristics that require proper maintenance over their service life.
Modified bitumen has become a conventional alternative to built-up roof systems. As usage increases, roofing contractors will not only be required to install these systems, they also will need to repair and maintain them.
There are two primary types of modified bitumen systems: atactic polypropylene (APP) and styrene-butadiene-styrene (SBS). Possible application methods are: torch applied, set in hot asphalt, set in cold adhesive and self-adhering systems. Each method has nuances that could contribute to potential problems. Modified materials also have inherent characteristics that require proper maintenance over their service life.