Built-up roofing (BUR) is a proven flat roofing system commonly used on commercial and low-slope residential buildings. It is a multi-layer system using asphalt and reinforcing felts, designed to create a thick, durable roofing membrane that stands up to water, UV exposure, and daily wear. BUR has been used for decades because of its reliable waterproofing performance and long-term value.
As a multi-layer system using asphalt and reinforcing felts, BUR is constructed by alternating layers of bitumen (asphalt or coal tar) with roofing felts or fiberglass sheets. These layers are built up to form a strong, watertight barrier, and the final surface is often finished with gravel or a reflective coating for added protection. The multiple layers provide redundancy, meaning the roof can still perform well even if one layer becomes damaged.
Built-up roofing is especially effective for roofs with heavy foot traffic, rooftop equipment, or areas that require extra durability. It offers excellent puncture resistance and can help protect against impacts from debris or maintenance activity. BUR systems can also support improved energy efficiency when paired with reflective surfacing or added insulation.
For property owners looking for a dependable and time-tested flat roof option, built-up roofing delivers strong performance. With a multi-layer system using asphalt and reinforcing felts, BUR provides long-lasting waterproof protection and durability that makes it a trusted choice for low-slope roofing systems.
