Built-Up Roofing for Commercial Buildings: Is It the Right Choice? Uncover the Pros and Cons
When it comes to choosing a reliable, long-lasting roofing system for a commercial building, Built-Up Roofing (BUR) often tops the list. Known for its layered durability and impressive weather resistance, BUR systems have been a go-to solution for flat or low-slope roofs for over a century.
But is this traditional roofing method still the best choice in today’s commercial landscape? Like any roofing system, built-up roofing comes with advantages and drawbacks that business owners, property managers, and contractors must weigh carefully.
What Is Built-Up Roofing (BUR)?
Built-up roofing (BUR) is a traditional and time-tested roofing system designed for flat or low-slope commercial roofs. It consists of multiple layers of bitumen—either asphalt or coal tar—alternated with reinforcing materials such as fiberglass mats or organic felts. These layers are constructed on-site to form a thick, cohesive membrane that is then finished with a top layer for added protection. This surfacing might include gravel, mineral cap sheets, or reflective coatings, each serving to enhance durability and shield the roof from environmental exposure.
The strength of BUR lies in its layered construction, typically using three to five plies to create a resilient, long-lasting barrier. This composition provides exceptional waterproofing, fire resistance, and protection from harmful UV rays, making it a dependable choice for high-traffic or high-performance commercial buildings. BUR systems are widely used in facilities like warehouses, retail centers, office complexes, and municipal buildings, where proven performance and longevity are key priorities.
Why Built-Up Roofing Is a Smart Choice for Commercial Buildings
1. Outstanding Durability and Longevity
Built-up roofing (BUR) systems are known for their robust construction, featuring multiple layers of asphalt-saturated felts or mats that form a thick, protective barrier. This multi-ply system offers superior resistance to hail, heavy winds, foot traffic, and flying debris. With consistent maintenance and proper installation, BUR can reliably last 20 to 30 years—making it one of the longest-lasting options in commercial roofing.
2. Waterproofing Excellence
One of BUR’s standout features is its exceptional waterproofing ability. Each added layer reinforces the system’s defense against water intrusion. When topped with gravel or a mineral-surfaced cap sheet, the system effectively sheds water and resists ponding, leaks, and moisture buildup. This makes it especially advantageous for flat or low-sloped roofs in regions prone to heavy rain or snow.
3. Fire and UV Resistance
BUR systems are frequently rated Class A for fire resistance—the highest rating available—thanks to their layered design and protective top surfacing. Additionally, when finished with reflective coatings or mineral cap sheets, BUR reduces UV penetration, helping to mitigate heat absorption and extend the life of the roof by preventing material degradation over time.
4. Energy Efficiency
When paired with reflective surfacing or integrated insulation, BUR roofing can significantly contribute to a building’s energy efficiency. Reflective coatings help reduce heat gain, keeping interior temperatures more stable and lowering cooling costs. This makes BUR not only durable but also a practical solution for facilities aiming to improve energy performance.
5. Low Maintenance and Repairable
While no roofing system is entirely maintenance-free, BUR is relatively easy to manage over time. Small issues such as blisters, cracks, or minor punctures can often be repaired locally without needing to overhaul the entire system. This repairability adds to BUR’s value, offering a cost-effective way to maintain a watertight and resilient roof over the long term.
Drawbacks to Consider Before Choosing BUR
1. Heavier Roof Load
BUR’s layered structure makes it significantly heavier than modern single-ply or membrane roofing. Buildings with limited structural capacity may require reinforcement, adding cost and complexity.
2. Complex and Lengthy Installation
Installation involves multiple hot-applied layers, which means longer project timelines and potential business disruption. Additionally, hot asphalt releases strong odors and fumes, which may be inconvenient or unsafe during installation.
3. Higher Upfront Cost
While cost-effective over time, BUR typically costs more initially due to labor, materials, insulation, and structural requirements compared to lighter systems like TPO or EPDM.
4. Limited to Low-Slope Applications
Built‑Up Roofing systems are intended for flat or low-slope roofs. Drainage and runoff issues make BUR unsuitable for steeper roofs, which may perform better with single-ply or metal systems.
Critical Considerations for Built-Up Roofing Installation
When evaluating roofing options for a commercial property, understanding how your roof will function under daily demands is essential. Built-up roofing (BUR) is especially well-suited for buildings that experience regular foot traffic, house rooftop equipment, or require frequent maintenance access. Its layered construction offers durability and impact resistance, making it a reliable solution for active roof environments.
Climate is another major factor to consider. BUR performs exceptionally well in regions with heavy rainfall, snow accumulation, or intense UV exposure. The system’s waterproofing strength and resistance to thermal stress make it ideal for protecting commercial structures in challenging weather conditions. While the upfront cost may be higher than some alternatives, BUR offers excellent long-term value by minimizing the need for frequent repairs or early replacement.
It’s also important to weigh the potential impact on your day-to-day operations. The installation process for BUR can take time and may involve strong odors from bitumen application, which could disrupt business activities if not properly managed. Additionally, due to its multi-layered structure, BUR adds weight to the building. Before moving forward, have a structural assessment completed to ensure your facility can handle the additional load safely. Careful planning in these areas will help you make a confident, informed decision.
Why BUR Remains a Trusted Roofing Solution
When it comes to selecting the right roofing system for a commercial property, Built-Up Roofing (BUR) continues to stand out as a time-tested, high-performance option. Its multi-layered construction offers exceptional durability, reliable waterproofing, and superior fire resistance—making it particularly well-suited for flat or low-slope buildings that demand long-term protection. For property owners seeking stability and proven results, BUR delivers.
While the system involves a more complex installation process, carries additional weight, and may require a higher initial investment, the long-term benefits often outweigh the upfront costs. With proper maintenance, BUR can significantly reduce repair needs and extend the life of your roof. If your goal is to invest in a roofing system built for endurance, safety, and minimal upkeep, Built-Up Roofing may be the ideal solution for your commercial building.