Redundant By Design
Three or more waterproofing plies mean a defect in one layer never reaches the building below.
Roofing Systems
Built-Up Roofing
The century-old standard — multiple plies of reinforced asphalt building a roof with redundancy no single layer can match.
System Overview
Built-Up Roofing, Explained
Built-up roofing — the classic ‘tar and gravel’ system — is field-fabricated from alternating layers of bitumen and reinforcing felts, typically three plies or more, finished with aggregate or a reflective surfacing. It’s one of the most thoroughly documented systems in American roofing, with a performance record stretching back over a century.
That documented history is why BUR still gets specified on institutional and government buildings where long service life carries real weight. The layered assembly also delivers thermal mass and outstanding puncture resistance on roofs that see heavy traffic.
At A Glance
System Specs
Service Life
20–30+ Years
Slope
Low-Slope
Plies
3–5 Layers
Surfacing
Gravel · Reflective Cap
Best For
- Government & institutional
- Schools & universities
- Buildings held long-term
- High-traffic roof areas
Why Owners Choose It
- Redundant By Design. Three or more waterproofing plies mean a defect in one layer never reaches the building below.
- Century of Proof. No commercial system has a longer documented track record — a real factor for owners planning in decades.
- Tough Surface. Aggregate surfacing resists punctures, foot traffic, and UV — protection membrane systems need added materials to match.
Key Advantages
Where Built-Up (BUR) Wins
Century of Proof
No commercial system has a longer documented track record — a real factor for owners planning in decades.
Tough Surface
Aggregate surfacing resists punctures, foot traffic, and UV — protection membrane systems need added materials to match.
Common Questions
Straight Answers
No — it’s specified less often than single-ply because of installation cost, but on buildings owned for generations its redundancy and track record still make a strong case. We’ll tell you honestly whether it fits your building and budget.
Frequently, yes. A sound, dry BUR assembly is an excellent candidate for restoration coatings that add years of service at a fraction of replacement cost.
