Built-up roofing or BUR has been around since the 1870’s and is the oldest low-slope roofing system still used in the United States. When installed correctly, BURs can last from 20-30 years. This roof type’s base material is tar and can be installed with or without gravel as a top layer. With the right size of gravel, it can be one of the most hail-resistant roofing systems on the market today.
One of the disadvantages of a built-up roof, however, is its weight. A BUR can weigh up to 600 pounds per roofing square (or 6 pounds per square foot). The tar-based material can also cause it to be very energy inefficient. Something else to take into consideration is that fast and large temperature changes (like we have in Texas) can cause thermal shock. These rapid changes in temperature can cause the tar to crack. Because of these drawbacks, built-up roofing is typically not the best roofing option in Texas.