This type of roofing is a commonly applied flat roof solution for people looking towards an easy to install solution. Modified bitumen is essentially rolls of black product that overlap one another to form a water tight barrier. These rolls are “modified” with polymers giving it rubber or plastic like qualities. The surface of modified roofing is mostly smooth, however there are many products on the market now that come granulated. This is where some type of slag is applied often roofing granules to achieve a color match with an asphalt roofing shingle.
Applications: Low sloped residential or commercial roof surfaces.
Installation: Installing modified rubber bitumen roofing is for the most part a simple surface, there are essentially two kinds. There is modified roofing that uses a base sheet material and is simply a peel and stick solution. Then there is torch down. Where as the product is rolled out and a heat torch applied which melts the asphalt on the underside of the roll and adheres it to the roofing deck. The “self stick” product has become the most popular in recent years.
Pro’s: Some of the advantages to modified rubber bitumen roofing is its relative ease of installation. Forgiveness of the product. Modified roofs can be walked on without any special considerations. They are also suitable for flat roof systems with next to no slope required although it’s always best to get the water off. Often times when the roof gets to the end of its usable life you can coat the product to prolong it usefulness, please refer to the roof coatings sections.
Con’s: Leaks in modified rubber bitumen systems can be hard to track down. It is not the longest lasting flat roof solution with some reported failures inside of 10 years depending on quality of installation and maintenance.
Modified bitumen roofing cost and pricing information
Cost: This roofing product is certainly on the lower end of raw material cost with prices per square to be found at $75 or less. It is important to keep in mind that this cost can significantly balloon when you look at base sheets, removal of old roofing, deck preparation, hiring a contractor etc…