These roof assemblies have a good life expectancy, normally in the range of 15 to 25 years. Built-up roofs were very popular until the I 970’s, enjoying better than 90% of the roofing market. For a variety of reasons BUR’s experienced a decline in the market to approximately a 40% share in 1989. Significant improvements in materials, and a better understanding of proper application techniques have resulted in significant gains in overall performance as well as market share. Approximately 55% of the commercial roofing market is now BUR again.

Asphalt BUR’s are best utilized when roof areas have significant slope where the low melting point of coal tar might cause "slippage" of the membrane. Normally any roof system which has in excess of 1/4" per running foot of slope should utilize asphalt if the building owner wishes to utilize a built- up system. Asphalt roofs can also be built in a "smooth surface" installation if the finished surfacing of gravel is undesirable to a client.