Asphalt Built-up Roofing can be used in both new construction and existing buildings. This system gets the name “built-up” because of the multiple layers of alternating asphalt and saturated felts or fiberglass mat roofing plies.
These systems can be long lasting and durable when properly installed with quality bitumen, felts and flashings. Surfaces (gravel, coatings, or granules) extend the life of a BUR roof by providing weatherproofing and protection from UV exposure.
BUR systems have low flexibility and therefore are only appropriate on roof decks with minimal movement. BUR systems require periodic maintenance to maximize their service life.
Coal Tar Pitch
Coal Tar built-up roofing provides one of the most durable roofing systems known due to its inherent waterproofing and weathering characteristics. Similar to asphalt BUR, coal tar BUR consists of multiple layers of alternating coal tar and saturated felts and topped with a flood coat and gravel surface. Coal Tar is limited to level and low slope roofs. Coal tar has a relatively low softening point so it must always include a gravel surface.
Coal Tar roofing is self-healing. Due to the low softening point, on warm days it will actually flow and heal itself of minor cracks and punctures.
Coal tar roofing systems are a time-proven roofing system.