BUR (built-up roof) is an older type of system consisting of multiple layers of tar and asphalt material covered with gravel or gravel granules. The system is designed to provide three main components: structural, waterproofing and a surface. The expected service life of a BUR system is around 12 years with extensive maintenance. As with Modified Bitumen roof systems, ponding water is very detrimental and commonly causes blisters. Blisters are a result of the heating of water vapor trapped in the roof system and if ignored, blisters become worse over time. This is an indication of water penetrating one or more of the layers in the roof system. In addition to the initial high cost of installation, most contractors no longer have the specialized equipment to install a new BUR system.
Thermo Manufacturing can provide a long-term, sustainable solution for difficult roofing conditions. The links below cover our standard recommended systems for BUR roofs.
If actual project conditions are such as to be outside the scope of the normal waterproofing practices that are referenced in the documents below, steps should be taken to ensure the restoration remains in compliance with nationally recognized waterproofing practices such as those found in the National Roofing Contractors Association Manual. If the system is applied according to our published specification and guideline, and after successfully passing a final inspection, and then accepted by Thermo Manufacturing Systems, LLC, the system would qualify for the specified warranty.