What role does the gravel serve in BUR systems?

In Built-Up Roofing (BUR) systems, gravel serves a crucial role in providing UV protection and enhancing drainage. The coarse aggregate of gravel reflects UV radiation, thereby protecting the underlying layers of the roofing membrane from the damaging effects of sun exposure. This reflection helps to prolong the life of the roofing materials by preventing degradation and extending their effective lifespan.

Additionally, gravel plays an important role in drainage by allowing water to flow off the roof surface and preventing pooling, which can lead to leaks or other damage. The aggregate assists in promoting proper drainage by creating a slope and reducing the chance of water accumulation.

While gravel can provide a decorative finish and potentially contribute to stability by adding weight, its primary functions focus on UV protection and effective drainage, which are essential for maintaining the integrity and longevity of a BUR roofing system.