What is built-up roofing (BUR)?

Built-up roofing, or BUR, is a time-tested flat roof system that layers tar-saturated felt sheets with hot bitumen (asphalt or coal-tar pitch), finishing with a gravel cap. The multiple plies, typically three to five, create a watertight membrane that distributes stress across the whole surface rather than relying on seams.

BUR remains common on older commercial buildings, warehouses, and industrial facilities across Greater Hartford. The gravel top layer serves two purposes: it reflects UV radiation to extend roof life and provides fire protection. Because flat roofs are standard on many commercial structures in the region, BUR still represents a familiar and often economical option for buildings built in the 1960s through 1990s.

The system performs well when properly installed and maintained, though it requires regular inspections to catch membrane damage and ponding water. Modern alternatives like single-ply membranes (TPO, EPDM) and spray polyurethane foam have gained market share, but BUR remains viable for straightforward roof designs and where weather resistance over decades is the priority. Contractors familiar with BUR installation and repair are an asset for property managers maintaining existing flat-roof commercial stock in the Hartford area.