Built-Up Roofing in Toronto

Built-up roofing is often called BUR or “tar and gravel” roofing. Basically, the roofing material is layered from the bottom to the top, thus the term “built-up. If the roof is made of wood, a base layer like a rosin sheet or base sheet is mechanically fastened on the roof deck before layering the roofing material. In case of steel roof decks, the material can be fully adhered to roof decks provided the steel is at least 22-gauge.

Once the base layer is secure, layers of fiberglass matting or organic felt saturated in bitumen or polymers called a membrane is adhered to the roof, alternating it with bitumen. This is built up into three or four layers, alternating membrane with bitumen or tar which serves as a laminating layer. The asphalt also acts as a waterproofing layer, adding to the durability and weatherability of a built up roof. It is then topped off with a surfacing layer or top layer which can be made of asphalt, gravel or slag. Sometimes a granule-surfaced cap sheet is also used.

​The layers of membrane, bitumen and minerals make built-up roofing systems extremely durable and can withstand even the harshest weather. Installed properly, BUR can resist wind, hail, snow and even UV rays. It offers excellent insulation, making it an energy efficient choice that can lower heating and cooling costs. Perhaps one of the most important benefits of a BUR system is the redundancy it provides due to its multiple layers. Built-up roofing systems in Toronto are time and weather tested.