Built-Up Roofing (BUR) is one of the oldest and most time-tested commercial roofing systems, consisting of multiple layers of bitumen (asphalt or coal tar) alternated with reinforcing fabrics like fiberglass or organic mats. The system is finished with a top layer of gravel or a reflective coating to protect against sun and weather. BUR is typically used on low-slope or flat roofs and is valued for its layered protection, redundancy, and excellent waterproofing capabilities.
Pros of BUR Roofing in the Las Vegas Climate
- Excellent Waterproofing: Multiple layers of bitumen and felts create a dense, watertight membrane, making BUR highly resistant to water intrusion during rainstorms.
- Durability and Longevity: When properly maintained, BUR systems can last 20–30 years or more, holding up well under Las Vegas’ intense sun and fluctuating temperatures.
- Good Fire Resistance: The top gravel layer and use of non-combustible materials provide solid fire protection, which is especially important in Southern Nevada’s dry climate.
- Cost-Effective for Large Flat Roofs: For expansive commercial roofs, BUR can be a cost-efficient option when spread over large areas.
- UV Protection: The gravel or coating layer helps shield the underlying membrane from damaging UV rays.
- Redundancy in Protection: The multiple plies offer extra layers of defense—if one is damaged, others still provide coverage.
Cons of BUR Roofing in the Las Vegas Climate
- Can Be Heavy: BUR systems add significant weight to a structure, which may require structural reinforcement—especially in retrofits.
- Installation is Labor-Intensive: Requires skilled labor, hot tar or bitumen application, and extended installation time, which can be disruptive to building occupants.
- Susceptible to Ponding Water: Flat roofs with improper drainage can accumulate standing water, which may degrade the system over time.
- Heat Absorption: Traditional dark-surfaced BUR systems may retain heat unless a reflective coating is applied, potentially increasing cooling demands.
- Odor During Installation: The use of hot asphalt or tar can produce strong odors, which may be disruptive during application.
Where BUR Roofing is Commonly Used in Las Vegas
BUR remains a reliable choice for many larger and older commercial buildings, especially those with wide, flat rooftops and robust structural support:
- Older Industrial Facilities
- Public Schools and Universities
- Large Retail Stores and Supermarkets
- Municipal and Government Buildings
- Commercial Buildings with Existing BUR Systems (looking for repair or replacement in-kind)
For property owners seeking a proven, time-tested system with great waterproofing and fire protection, BUR is still a viable and often cost-effective solution—especially when maintained properly.