Flat roofs often bring to mind the tops of commercial buildings with their large AC systems. However, they are also popular among residential homes for the modern touch they add to a home's design. For this project, I completed a flat roof replacement in Newport Beach.
At this home, I replaced the worn BUR (Built Up Roof) system with a new Modified Bitumen Membrane. BUR systems are recognizable for their rock and gravel finish. It uses multiple layers of tar and gravel to provide the watertight seal with a top layer of gravel to serve as both a final barrier and reflective coating. It is one of the oldest types of flat roof systems available.
The Modified Bitumen roof, like BUR, is also an asphalt roofing system. The name Modified Bitumen comes from the thermoplastic or rubber polymers used to reinforce and modify the asphalt in the membranes. These added polymers provide some additional benefits to Modified Bitumen roofs.
For this project I used the torch-applied or "torch-down" method on the APP Cap Sheet, the final layer on the home's new Modified Bitumen system. APP, or atactic polypropylene, is the thermoplastic polymer that provides the same reflective coverage as the final layer of gravel on a BUR system.
What used to be 2 layers on a BUR system is combined into one in a Modified Bitumen Membrane. Homeowners no longer have to worry about maintaining an even gravel layer on their roofs to repel the sun's harsh rays and prevent cracks. The Modified Bitumen can also handle a wider temperature range because of the flexibility of the material. Unlike BUR, it can handle both hot and cold temperature extremes. This helps with keeping both heat and moisture away from the underlying layers.
I have over 30 years of experience installing torch-applied roofing systems and give the utmost attention to ensuring a water-proof seal at critical flat roof areas. Contact us for a free estimate at Alas & Bravo Roofing.