Roof system
Built-Up Roofing (BUR) explained
A built-up roof alternates layers of bitumen (asphalt or coal tar) with reinforcing felts to form a thick, redundant membrane. A top layer of gravel, slag or mineral granules protects it from sun and weather.
Many older commercial buildings still have BUR roofs. When they reach the end of their life, owners can repair, restore or replace them with a modern system.
Warning signs
When to Call Blackstone
- Bare spots where gravel has moved
- Blisters or splits in the membrane
- Cracked flashing
- Ponding water
- Leaks at drains and penetrations
- Soft spots when walking
How we help
What Blackstone Does
BUR repair
Patching splits, blisters and failed flashing.
Replacement
Tear-off and installation of a new BUR or modern single-ply system.
Moisture surveys
Finding wet insulation before deciding between repair and replacement.
Questions
Built-Up (BUR) FAQ
Should I replace BUR with BUR?
It depends on the building. Many owners switch to TPO, PVC or modified bitumen. We compare the options with you.
What is the gravel for?
It protects the asphalt from UV and adds fire resistance.
Can a BUR roof be coated?
Some can, after the gravel is removed and the surface prepared.
Related
Related Services
Talk to Blackstone
Get a Free Inspection
Tell us what is going on with your property. A project manager will follow up with next steps.



