Built up roofing (BUR) is a traditional roofing system used extensively for flat or low-slope roofs. Originating in the 19th century, a built up roof consists of multiple layers of bitumen and reinforcing fabrics, creating a durable and watertight membrane. Typically found on commercial, industrial, and institutional buildings, built up roofing is renowned for its longevity and reliability. Its multi-layer construction provides excellent protection against the elements, making it a popular choice for buildings requiring robust waterproofing and fire resistance. The combination of durability, performance, and adaptability to various building types continues to make built up roof a favored option for modern roofing needs.
A built-up roof system comprises several key components, each contributing to its durability and effectiveness:
These components work together to form a robust, long-lasting roofing solution.
The installation process of a built-up roof begins with preparing the roof deck, ensuring it is clean, dry, and structurally sound. The base sheet is then adhered to the deck. Multiple layers of ply sheets are laid, with each layer bonded using hot bitumen. This layering process continues until the desired thickness is achieved. Finally, a surfacing layer of gravel, slag, or a reflective coating is applied for UV protection and durability. Weather conditions are critical; installation should be done in dry conditions. Safety measures, including protective gear and proper handling of hot bitumen, are essential throughout the process.
Built-up roofs provide several significant benefits that make them a popular choice for many building types:
Built up roofing systems are renowned for their long lifespan and robustness, often lasting 20 to 30 years or more with proper maintenance. The multiple layers of bitumen and reinforcing fabrics contribute to their strength, making them resistant to various forms of damage, including impact and wear from foot traffic.
One of the primary advantages of a built up roof is its superior resistance to water penetration. The bitumen layers create a continuous, watertight barrier that effectively prevents leaks and water damage, even in heavy rain conditions.
Many built up roofing materials, such as asphalt and gravel, offer excellent fire protection. These materials can help prevent the spread of flames and provide additional safety for the building’s occupants and contents.
Built up roofing systems have good insulation properties, which help to regulate building temperatures. The multiple layers act as a thermal barrier, reducing heat transfer and improving energy efficiency. This can lead to lower heating and cooling costs, making the building more comfortable and economical to operate.
These benefits collectively make a built up roof ideal for commercial and industrial buildings that require a durable, waterproof, and thermally efficient roof. For a long time, the combination of longevity, effective waterproofing, fire resistance, and insulation performance ensured it to be one of the most effective roofing types. It still can be effective, but it is important to consider the downsides that come with the benefits.
Built Up Roofing (BUR) systems are heavier than many other roofing options, such as single-ply membranes. The multiple layers of bitumen and reinforcing materials add significant weight to the structure, which necessitates a strong and well-engineered building frame. Older buildings or those not designed to support such loads may require structural reinforcement, adding to the overall cost and complexity of the project.
Leaks are hard to find in built-up roofing due to its complex structure. Built-up roofs consist of multiple layers of bitumen and reinforcing fabrics, topped with a layer of gravel or other aggregate. This multi-layered design creates a dense and opaque surface, making it challenging to pinpoint the exact location of a leak. Additionally, the loose gravel layer adds another obstacle, as it needs to be removed or displaced to access the roofing material beneath. The leak may travel between the layers before becoming noticeable inside the building, further complicating detection and repair efforts. This complexity demands thorough inspection and expert knowledge to identify and fix leaks effectively.
Installing a built-up roofing system is a complex process that requires skilled labor. The application of bitumen, especially when hot-applied, demands expertise to ensure proper adhesion and layering. Additionally, the installation must be conducted under specific weather conditions, typically dry and warm, to prevent issues with the bitumen setting correctly. This can limit the installation windows and potentially delay the project.
The application of bitumen can produce strong odors and hazardous fumes, which can be a concern for both workers and building occupants. Proper ventilation and safety measures are essential during installation to minimize exposure to these fumes. In some cases, these odors can linger, causing discomfort.
A built up roof requires regular inspections and upkeep to maintain its integrity and performance. Over time, the surfacing layer (such as gravel) can become displaced, and the bitumen can develop cracks or blisters. Regular maintenance is crucial to address these issues promptly and prevent more significant problems, such as leaks or structural damage.
Overall, built-up roofing systems are durable, lasting 20 to 30 years, and offer excellent waterproofing, fire resistance, and thermal performance, making them ideal for commercial and industrial buildings. However, their popularity has declined due to several disadvantages. They are heavy, requiring strong structural support, and their multi-layered design makes leak detection difficult. Installation is complex, labor-intensive, and weather-dependent, generating strong odors and hazardous fumes. Regular maintenance is necessary to address issues like displaced gravel and cracked bitumen. These factors contribute to their decreased use in favor of more modern, lightweight, and easier-to-install roofing options.
When comparing Built-Up Roofs with other roofing systems, each has its unique strengths and best-use scenarios.
Single-Ply Membranes (TPO, EPDM, PVC):
– TPO (Thermoplastic Olefin): Known for its energy efficiency and reflective properties, making it excellent for reducing cooling costs in hot climates.
– EPDM (Ethylene Propylene Diene Monomer): Offers superior flexibility and weather resistance, ideal for varying climates and structures requiring lightweight roofing.
– PVC (Polyvinyl Chloride): Provides strong chemical resistance and durability, perfect for roofs exposed to harsh chemicals or pollutants.
Modified Bitumen (SBS, APP):
– SBS (Styrene-Butadiene-Styrene): Combines flexibility with strong performance in cold temperatures, making it suitable for climates with significant temperature fluctuations.
– APP (Atactic Polypropylene): Offers enhanced UV resistance and durability, ideal for areas with high sun exposure.
Built-Up Roofs excel in providing robust, long-lasting waterproofing and excellent fire resistance, making them suitable for commercial and industrial buildings where durability and safety are paramount. A built up roof is best for structures that can support the added weight and where long-term maintenance is manageable.
Routine maintenance for Built-Up Roofs includes regularly clearing debris to prevent water pooling and inspecting the surface for damage like cracks, blisters, or punctures. Inspections should be conducted at least twice a year and after severe weather events to identify any potential issues early. Common repairs involve patching leaks with additional layers of bitumen and fabric, addressing blisters by cutting and sealing them, and replacing worn or damaged sections. Prompt attention to minor issues can prevent more extensive and costly damage, ensuring the roof remains in good condition and extends its lifespan.
Built-Up Roofs (BUR) have several environmental considerations. The materials used, such as bitumen and reinforcing fabrics, can be recycled, contributing to material sustainability. BUR systems enhance a building’s thermal performance due to their excellent insulating properties, leading to reduced energy consumption for heating and cooling. Additionally, the potential for recycling old roofing materials helps minimize waste and reduce the environmental footprint. Choosing sustainable surfacing options, like reflective coatings, can further improve energy efficiency by reducing heat absorption, making BUR an environmentally responsible choice for commercial and industrial buildings.
A Built-Up Roof (BUR) entails several cost considerations. Initial installation costs include labor, materials like bitumen and reinforcing fabrics, and specialized equipment for application. While the upfront investment can be higher than some roofing options, BUR’s durability and low maintenance requirements often result in long-term savings. Factors influencing costs include the size of the roof, material choices (such as gravel or reflective coatings), and prevailing labor rates in the region. Choosing high-quality materials and professional installation can optimize performance and minimize lifecycle costs, making BUR a cost-effective solution for many commercial and industrial buildings.
In conclusion, a built up roof offers a robust solution for flat or low-slope roofs. However, due to improvements in technology, built up roofing is no longer the most popular choice. The system’s multiple layers of bitumen and reinforcing materials provide long-lasting protection against weather elements and mechanical damage. Key advantages include its longevity, with proper maintenance extending its lifespan significantly. Built up roof systems also enhance energy efficiency and environmental sustainability through their insulating properties and recyclable materials.
When considering built up roof systems for a project, it’s essential to evaluate factors. Such factors include the building’s structural capacity to support the roof’s weight and the specific environmental conditions of the site. While installation costs may be higher initially, the potential for long-term savings in maintenance and energy costs makes a built up roof system a cost-effective choice over its lifecycle.
For projects where durability, reliability, and low maintenance are priorities, built-up roof systems stand out as dependable options. Proper installation by experienced professionals and regular maintenance are crucial to maximize the system’s performance and lifespan. By weighing these factors and consulting with roofing experts, stakeholders can make informed decisions about integrating BUR into their building projects, ensuring lasting protection and value for years to come.
Discover the strength and reliability of Built-Up Roofs (BUR) with Troyer Commercial Roofing. Ensure your commercial or industrial building is well-protected with our skilled installation and maintenance services. Schedule a free roof inspection today to assess your roofing needs and learn about the benefits of BUR, including excellent waterproofing, energy efficiency, and sustainability. Our Conklin-certified team will provide personalized insights and recommendations based on your project’s requirements. Contact us and find out which roofing type is the best solution for your commercial roof.
