Built-up roofs are typically referred to as tar and gravel roofs.  They are one of the oldest and most reliable methods for roof installation.  It has been in use since the 1840’s.  BUR application is common on large Colorado commercial roofs, flat garages, Denver flat roofs on a home, etc.  BUR is applied in coats of hot asphalt to several layers of roofing felt; this embeds the felt to the asphalt while the asphalt is still hot.  This process is continued until the desired number of layers is achieved.  Your Denver roof can have three to five plies, four being typical.  Then gravel is added to the roof to reflect Colorado’s ultra-violet radiation from the sun. It also helps spread rainwater across the roof.   BUR is a continuous process and everything must be installed in a single day.

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A built-up roof will typically have a roof life of 15-25 years depending on the number of plies, weather conditions, materials used, geographical location and foot traffic.  A good rule of thumb to determine a BUR’s roof life is 5 years for every ply installed.  For example a 3 ply roof should have a life span of 15 years, a 4 ply roof should have a life span of 20 years and a 5 play roof should have a life span of 25 years.

Roof Worx is your Colorado roofer with years of experience and knowledge ideal for your Denver commercial building or the flat roof on your Colorado home.  Give them a call today at (303) 353-1825.