Modified Bitumen Services
Modified Bitumen (MB) sheet membranes have been in use in the United States since the mid-1970s. Modified roof membranes are composed of reinforcing fabrics that serve as carriers for the hot polymer-modified bitumen as it is manufactured into a roll material. MB roof system membranes are composed of multiple layers, much like BUR membranes. MB roof systems typically are installed as a two-ply system and almost always are fully adhered.
There are two types of MB roofing membranes:
SBS polymer-modified bitumen membranes commonly are installed in hot moppings of asphalt (similar to BUR systems) or cold adhesive. Some SBS modified membranes are self-adhering; that is, they contain an adhesive backing.
APP polymer-modified bitumen membranes typically are heat-welded or torch-applied. Consumers should be cautioned that NRCA does not recommend torch-applying a modified bitumen membrane sheet directly to a wood deck. (NRCA, 2012)
We apply torch-down MB Systems as well as self-adhered MB systems, depending on the property characteristics.
Self-adhered products are a popular product for residential applications as they can be purchased with granule colors that closely match composition shingles, do not contain fumes associated with hot asphalt applications, and are quicker to apply in smaller quantities.
Key benefits of Modified Bitumen products:
Durable and puncture resistant
A proven product
Will closely match shingle color and composition
Flexibility in application methods without performance implications