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Modified Roof Systems

Modified Bitumen (MB)is asphalt that has had modifiers added to it to give it plastic or rubber-like properties. The most cocmmon types of modifiers being used are APP (Atactic Polypropylene) and SBS (Styrene Butadiene Styrene). Rolls of modified bitumen membrane come in widths of 36” to approximately 39” and cover an area of approximately 100 square feet to 112 square feet. Surfacings for these roll materials consist of mineral granules, aluminum, copper, or an aggregate such as gravel or slag.

Modified Bitumen roof systems consist of one, two, or three ply systems. The type of substrate will often determine the type of system being installed. Modified membranes can also be installed in conjunction with built-up roof materials (such as multiple plies of fiberglass felt) to form a hybrid roof system. Modified have proven performance on residential, commercial, and industrial applications.

There are two types of MB roofing membranes:

     - SBS polymer modified bitumen membranes are installed in hot moppings of asphalt or cold adhesive. Some SBS        modified membranes are self adhering; that is, they contain an adhesive backing.

     - APP polymermodified bitumen membranes typically are "heat welded" or applied using a torch. Consumers should        be cautioned that NRCA does not recommend torch applying a modified bitumen membrane sheet directly to a        wood deck.

Give us a call at (818) 773-9471 or (800) 805-ROOF (7663), to request more information or to receive a free estimate. We will make every effort to provide you with the specialized service that you need.