Commercial built-up roofing (BUR) is a roofing system composed of multiple layers of asphalt or tar and reinforcing materials, such as fiberglass or felt, that are applied in alternating layers directly on the roof. These layers, known as “plies,” are topped with gravel or a reflective coating to provide additional protection against UV rays and weather. Built-up roofing is known for its durability, excellent waterproofing capabilities, and resistance to heavy foot traffic, making it a popular choice for flat or low-slope commercial roofs. This multi-layer system is particularly effective at providing long-term protection against harsh weather conditions and general wear and tear.
Commercial Roofing Los Angeles offers professional built-up roofing (BUR) services to businesses in Los Angeles and the surrounding areas. Specializing in installing durable, multi-layered BUR systems, they provide long-lasting protection for commercial buildings with flat or low-slope roofs. Their built-up roofing solutions are designed to withstand the region’s varying weather conditions, offering excellent waterproofing and UV resistance. With a commitment to quality and reliability, Commercial Roofing Los Angeles ensures that your commercial roof is built to perform for years to come.
What Is Commercial Built Up Roofing?
Commercial built-up roofing (BUR) is a dependable flat or low-slope roofing solution frequently installed on commercial properties. It is constructed using alternating layers of bitumen, such as asphalt or coal tar, and reinforcing fabrics, topped with an aggregate layer like gravel. This layered approach delivers excellent waterproofing and longevity, making it a preferred option for buildings exposed to diverse weather conditions. In Los Angeles, BUR systems are particularly beneficial because they perform well during periods of heavy rain while also resisting damage from the city's abundant sunlight.
A key advantage of BUR is its ability to form a durable, seamless barrier against water intrusion. This characteristic makes it ideal for commercial roofs experiencing high foot traffic or supporting heavy equipment, as the system can endure significant strain. According to the National Roofing Contractors Association, built-up roofing can have a lifespan of 20–30 years when properly maintained. Maintenance tasks, including regular inspections to identify issues such as cracks or blisters, are essential to extending its performance. In Los Angeles, BUR systems are often paired with reflective coatings to meet California’s Title 24 energy efficiency standards, reducing heat absorption and decreasing cooling expenses. This combination of strength, weather resilience, and energy efficiency makes BUR an excellent choice for many commercial properties in the region.
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Which Layers Make Up a Built-Up Roof System?
A built-up roof system consists of four essential layers: a base sheet, ply sheets, bitumen, and a surfacing layer. The base sheet provides a stable foundation, securely attaching to the roof deck. Ply sheets, made of reinforcing fabrics like fiberglass or organic materials, add flexibility and strength. Bitumen, typically asphalt, acts as an adhesive and creates a watertight barrier to protect against water infiltration. The surfacing layer, such as gravel or a reflective coating, shields the roof from UV radiation, extreme heat, and weathering. In Los Angeles, where intense sunlight and occasional rainstorms are prevalent, built-up roofs are favored for their durability and ability to handle these conditions. The Cool Roof Rating Council notes that surfacing options like reflective coatings can also help reduce energy costs in Southern California's climate.
- Base Sheet
- Ply Sheets
- Bitumen
- Surfacing Layer
1. Base Sheet
The base sheet is the foundational layer of a built-up roofing system, designed to protect the roof deck and support the entire structure. Installed directly onto the roof deck, it provides stability and ensures compatibility with the layers applied above. This layer is typically made from reinforced materials such as fiberglass or polyester, offering exceptional durability and resistance to environmental stress. In Los Angeles, where buildings face challenges from seismic activity, fluctuating temperatures, and occasional heavy rains, the base sheet plays a critical role in ensuring the roofing system remains intact. Its proper installation creates a smooth surface that minimizes movement, tearing, or separation of subsequent layers. This foundational step is essential for extending the roof’s lifespan and preventing long-term issues such as leaks or structural damage.
2. Ply Sheets
Ply sheets serve as the reinforcing backbone of a built-up roof, consisting of organic or fiberglass fabrics saturated with bitumen to form a cohesive and durable layer. These sheets significantly enhance the roof's strength and adaptability, enabling it to withstand stresses like heavy foot traffic, rooftop equipment, and the thermal expansion or contraction caused by Los Angeles' climate. Multiple layers of ply sheets are often applied to increase the roofing system's resilience, creating a thicker, more durable membrane. The National Roofing Contractors Association highlights that the redundancy of these layers not only improves waterproofing but also provides superior protection against physical damage. In commercial settings, this reinforcement is vital for maintaining a reliable barrier against external elements, ensuring long-term performance and structural integrity.
3. Bitumen
Bitumen serves as the core adhesive and waterproofing element in a built-up roofing system, effectively binding the layers together to form a seamless and durable membrane. It is typically applied in either hot or cold forms, saturating the ply sheets to ensure strong adhesion while preventing water infiltration. This characteristic is particularly important for flat roofs in Los Angeles, which are susceptible to water pooling during the rainy season. Additionally, bitumen’s flexibility helps it absorb minor shifts caused by thermal expansion and contraction, reducing the risk of cracks or separations in the roofing system. The Asphalt Roofing Manufacturers Association highlights that bitumen is capable of maintaining its water-resistant properties under prolonged exposure to environmental stress, making it a reliable choice for commercial buildings. Its ability to create a cohesive and impermeable barrier is vital for extending the life and performance of the roof.
4. Surfacing Layer
The surfacing layer is the topmost component of a built-up roof system, designed to shield the underlying layers from environmental stressors and enhance the overall functionality of the roof. Materials such as gravel, mineral granules, or reflective coatings are commonly used for this layer, each offering unique benefits. Gravel or granules provide physical protection against wear and tear caused by foot traffic, while reflective coatings help minimize heat absorption by deflecting sunlight. This is especially important in Los Angeles, where reducing heat gain complies with California Title 24 energy standards, contributing to lower cooling costs for commercial properties. Additionally, the surfacing layer prevents UV damage, which can degrade the bitumen and ply sheets over time. By reinforcing the roof’s resistance to weather, physical impact, and thermal stress, this layer plays a crucial role in improving energy efficiency, performance, and sustainability for commercial roofs.
What Are The Pros Of Built-Up Roofing Systems?
Built-up roofing (BUR) systems offer numerous advantages, making them a popular choice for commercial buildings. Their primary benefit lies in their durability and multi-layered design, which provides exceptional resistance to water infiltration, UV radiation, and physical wear. BUR systems are well-suited for flat and low-slope roofs, offering long-term performance and reliability. Additionally, they provide excellent insulation, which helps reduce energy costs and maintain interior comfort. In climates like Los Angeles, the reflective surfacing options can also comply with energy standards such as California Title 24, enhancing sustainability while reducing cooling demands.
- Durability and Longevity
- Water Resistance
- Thermal Performance
- Low Maintenance Requirements
- Customization Options
- Cost-Effectiveness Over Time
1. Durability and Longevity
BUR roof systems are renowned for their capacity to endure demanding environmental conditions, such as intense heat, prolonged rainfall, and heavy mechanical activity. The multi-layered design, comprising a base sheet, ply sheets, bitumen, and a protective surfacing layer, offers exceptional structural integrity. This robust composition allows BUR systems to maintain their effectiveness for an average of 20–30 years, provided they receive routine inspections and timely maintenance. Their resistance to wear and ability to handle temperature fluctuations make them an ideal choice for commercial properties in regions like Los Angeles. According to the National Roofing Contractors Association, the longevity of BUR systems often surpasses alternative options when installed and maintained correctly. By investing in these systems, property owners achieve long-term reliability, reducing the need for frequent replacements or repairs.
2. Water Resistance
The integration of bitumen and reinforced ply sheets in BUR systems creates a seamless, watertight membrane, effectively blocking water infiltration. This quality is particularly valuable for flat roofs, where inadequate drainage can lead to water pooling and structural damage. The Asphalt Roofing Manufacturers Association highlights that BUR systems excel in mitigating these risks by offering strong water resistance and dependable performance during heavy rains. Their design prevents common issues like leaks, which can lead to costly repairs or damage to underlying building components. In Los Angeles, where seasonal rainfall can challenge poorly designed roofs, BUR systems provide an effective solution for ensuring long-lasting protection. Regular maintenance, including clearing debris from drains, further enhances the roof’s ability to handle water exposure efficiently.
3. Thermal Performance
Built-up roofing (BUR) systems excel in thermal regulation due to their multi-layered construction, which provides effective insulation for commercial buildings. The bitumen and ply sheets act as thermal barriers, preventing heat transfer and stabilizing indoor temperatures. This reduces the reliance on HVAC systems, lowering energy consumption for heating and cooling. In Los Angeles, where energy efficiency is critical due to high electricity costs and environmental regulations, the thermal performance of BUR systems aligns with California Title 24 energy standards. Reflective surfacing options, such as gravel or mineral granules, further enhance the roof’s ability to deflect heat, ensuring a comfortable indoor environment while cutting energy expenses. Studies by the Cool Roof Rating Council emphasize that improved insulation can reduce energy use by up to 20% in commercial properties.
4. Low Maintenance Requirements
Although regular inspections are essential to monitor performance, BUR systems demand comparatively low maintenance thanks to their durable design. The reinforced layers of bitumen and ply sheets resist wear and tear, minimizing the need for frequent repairs. When minor issues such as cracks or blisters arise, they are straightforward to address without disrupting the roof's overall functionality. This ease of upkeep contributes to reduced long-term maintenance costs, making BUR systems a practical choice for commercial property owners. According to the National Roofing Contractors Association, well-maintained BUR systems can last up to 30 years, with minimal intervention required to maintain water resistance and structural integrity. Routine cleaning and debris removal further ensure the roof remains functional and free from drainage issues, preserving its performance over time.
5. Customization Options
Built-up roofing systems provide extensive customization options to meet various aesthetic and functional requirements. The surfacing layer can include materials such as gravel, mineral granules, or reflective coatings, allowing property owners to tailor the roof to their specific needs. Gravel enhances durability and resistance to wear, while reflective coatings significantly improve energy efficiency by reducing heat absorption. This is especially critical in Los Angeles, where compliance with energy efficiency regulations, such as California Title 24, is essential. The U.S. Department of Energy states that reflective surfacing can lower roof temperatures by up to 30 percent, resulting in substantial cooling cost savings. These flexible options make BUR systems suitable for a range of commercial applications, including industrial facilities and office buildings.
6. Cost-Effectiveness Over Time
Although the initial cost of a built-up roofing system may be higher than other roofing options, its long-term benefits make it an economical choice. The multi-layered design minimizes the need for frequent repairs, reducing maintenance expenses over time. Additionally, its insulating properties lower energy consumption for heating and cooling, a significant advantage in climates like Los Angeles. The Cool Roof Rating Council has reported that improved thermal performance can reduce annual energy costs by up to 20 percent. With an expected lifespan of 20 to 30 years when properly maintained, BUR systems provide a reliable return on investment. These qualities make them an excellent solution for commercial property owners seeking durability, efficiency, and long-term financial savings.
Are There Any Disadvantages Of Built Up Commercial Roofing Systems?
Yes, built-up commercial roofing systems have disadvantages which should be considered before installation. While they are durable and effective, the installation process can be time-consuming and labor-intensive, leading to higher initial costs. These roofs are heavy, requiring a strong structural foundation, which may increase the expense of roof reinforcements. They are also susceptible to damage from standing water if drainage systems are inadequate, as prolonged water pooling can compromise the integrity of the layers. Regular maintenance is necessary to address issues like cracks or blistering, especially in regions like Los Angeles where temperature fluctuations can cause stress on the roof. Despite these drawbacks, their longevity and performance often outweigh these challenges for many commercial properties.
- Time-Consuming and Labor-Intensive Installation
- Heavy Weight
- Susceptibility to Standing Water
- Regular Maintenance Requirements
- Vulnerability to Temperature Fluctuations
- Higher Initial Costs
1. Time-Consuming and Labor-Intensive Installation
Installing built-up roofing systems is a detailed and time-intensive process due to their multiple layers, each of which must be applied with precision. The base sheet, ply sheets, bitumen, and surfacing materials require careful placement and adherence to ensure structural integrity and longevity. This multi-step approach extends the duration of projects, particularly for expansive commercial properties, and demands skilled labor to achieve optimal results. According to the National Roofing Contractors Association, poor installation practices can significantly reduce the effectiveness of the roofing system, making expertise vital. Additionally, the labor-intensive nature of the process increases costs, making built-up roofs less attractive to businesses seeking rapid or low-cost solutions.
2. Heavy Weight
Built-up roofing systems are among the heaviest commercial roofing options due to their layered structure and the inclusion of materials like asphalt and gravel. This additional weight can impose considerable stress on a building’s framework, potentially requiring reinforcements, especially for older or lightweight structures. According to the Asphalt Roofing Manufacturers Association, these reinforcements can add up to 20% to the total project cost. Without adequate support, the roof’s structural integrity may be compromised, leading to long-term damage. Property owners are advised to engage structural engineers to assess the load-bearing capacity of their building before proceeding with a built-up roofing installation. While the weight contributes to the system’s durability, it also increases installation complexity and expense.
3. Susceptibility to Standing Water
Built-up roofs are engineered for water resistance but remain vulnerable to standing water due to their flat or low-slope design. Prolonged water pooling can accelerate the deterioration of the surfacing layer, increasing the chances of leaks and reducing overall durability. This issue is especially problematic in regions with significant rainfall, as inadequate drainage or clogged outlets can exacerbate pooling. According to the National Roofing Contractors Association, unresolved standing water can shorten a roof's lifespan by as much as 25%, adding to long-term maintenance costs. Preventive measures, such as installing effective drainage systems and scheduling regular roof inspections, help manage pooling and maintain the roof’s integrity. Clearing debris and promptly addressing drainage blockages are crucial steps in mitigating this disadvantage and ensuring optimal performance.
4. Regular Maintenance Requirements
Despite their durability, built-up roofs demand consistent upkeep to sustain their performance and avoid expensive repairs. Over time, issues like surface cracks, blistering, and granule loss can emerge, especially in high-traffic areas with heavy equipment such as HVAC systems. The Asphalt Roofing Manufacturers Association emphasizes that identifying and addressing these issues early can prevent them from developing into more extensive problems. Routine maintenance includes clearing debris, resealing damaged areas, and inspecting the surfacing layer for wear. Performing biannual inspections and following recommended care protocols are essential to preserve the roof’s structural integrity. With diligent maintenance, built-up roofs can provide reliable protection and extended service life, making them a long-term asset for commercial properties.
5. Vulnerability to Temperature Fluctuations
Built-up roofing systems are susceptible to the effects of extreme temperature variations, particularly in areas experiencing significant seasonal changes. Prolonged exposure to intense heat can cause the bitumen layer to soften, leading to potential deformation or loss of adhesion between layers. Conversely, freezing temperatures can cause the material to contract and crack, compromising the roof’s water resistance and structural integrity. These temperature-induced stresses may result in more frequent repairs or reduce the system’s overall lifespan. According to the Asphalt Roofing Manufacturers Association, high-quality installation and the use of reflective or protective coatings can minimize these vulnerabilities by reducing heat absorption and improving the system’s resilience. Scheduling regular inspections to identify early signs of thermal damage ensures the roof remains functional and durable.
6. Higher Initial Costs
The initial investment for built-up roofing systems is often higher than other commercial roofing options due to the material-intensive and labor-demanding installation process. Each layer, including base sheets, ply sheets, bitumen, and surfacing, requires careful application to ensure proper adhesion and long-term performance. This meticulous process contributes to increased upfront costs, which can be a challenge for businesses operating within limited budgets. However, the durability and low maintenance needs of built-up roofing systems offer significant long-term savings, offsetting the initial expenditure over time. For example, data from the National Roofing Contractors Association highlights that businesses with well-maintained built-up roofs typically experience fewer repair costs compared to less durable alternatives. Property owners should carefully consider these long-term benefits when evaluating the financial feasibility of this roofing solution.
How Do You Install A Built-Up Roofing System?
Installing a built-up roofing (BUR) system involves a series of carefully executed steps to ensure durability, water resistance, and long-term functionality. The process begins by thoroughly cleaning and preparing the roof deck to establish a stable foundation for the system. A base sheet is then secured, offering initial stability and compatibility with the roof’s structure. Alternating layers of bitumen and reinforcing ply sheets are applied to create a robust, waterproof membrane. To complete the system, a surfacing layer, such as gravel or reflective coating, is added to protect against UV radiation, physical wear, and environmental elements. Each phase demands precision to ensure the roof meets the demands of commercial properties, particularly in Los Angeles, where intense heat and seasonal rains pose unique challenges.
- Prepare the Roof Deck
- Install the Base Sheet
- Apply Bitumen Layers
- Add Ply Sheets
- Repeat Layers as Required
- Install the Surfacing Layer
- Inspect the Completed Roof
1. Prepare the Roof Deck
Preparing the roof deck is the foundational step in installing a built-up roofing system. The process begins with a thorough cleaning to remove dirt, debris, or remnants of previous roofing materials that might hinder proper adhesion. A detailed inspection follows to evaluate the structural integrity of the deck, ensuring it is free from cracks, sagging, or other issues that could compromise stability. Repairs or reinforcements, such as replacing damaged sections or adding additional supports, are performed to establish a robust base for the roofing system. Proper preparation not only ensures smooth adhesion of subsequent layers but also prevents potential issues, such as water infiltration or structural failure, over the lifespan of the roof. According to the National Roofing Contractors Association, a well-prepared roof deck significantly contributes to the long-term durability of commercial roofing systems.
2. Install the Base Sheet
The base sheet is the first layer installed on the prepared roof deck and serves as the foundation for the entire built-up roofing system. Typically crafted from durable materials such as fiberglass or polyester, the base sheet enhances stability and creates a secure platform for the additional layers. It is either mechanically fastened using nails or screws or adhered with bitumen or specialized adhesives, depending on the design of the roofing system. This layer is crucial for absorbing minor movements in the structure caused by thermal expansion, contraction, or environmental factors, ensuring the system remains intact over time. In climates like Los Angeles, where temperature fluctuations and seismic activity are common, the base sheet plays a pivotal role in maintaining the roof's structural integrity. Precision during this step is vital, as improper installation can lead to premature wear or detachment.
3. Add Ply Sheets
Ply sheets serve as a critical reinforcement layer in built-up roofing systems, contributing to both durability and flexibility. Constructed from materials such as fiberglass or organic fabrics, they are embedded into hot or cold-applied bitumen to form a seamless connection with the base layer. This integration enhances the roof’s capability to withstand heavy foot traffic, rooftop equipment, and environmental stressors. Precise alignment and overlapping of the sheets are essential to eliminate gaps that might compromise the roof's resistance to water or wear. The National Roofing Contractors Association explains that properly installed ply sheets can significantly bolster a roof’s ability to endure cracking, tearing, and other forms of deterioration caused by structural or weather-related factors.
4. Repeat Layers as Required
To achieve the required thickness and durability, several layers of bitumen and ply sheets are applied to the roof. This step-by-step process builds a strong membrane designed to resist water intrusion, mechanical impact, and temperature fluctuations. Every layer must be applied with care, ensuring uniform distribution of bitumen and secure placement of ply sheets to maintain consistency. The number of layers added depends on the building’s specific needs, including expected load, climate challenges, and longevity requirements. The Asphalt Roofing Manufacturers Association highlights that a well-executed built-up system provides exceptional protection against leaks and extreme weather, making it a reliable choice for commercial buildings.
5. Repeat Layers as Required
Achieving the necessary thickness and durability of a built-up roofing system involves applying multiple layers of bitumen and ply sheets. Each layer is carefully embedded to strengthen the roof, offering increased resistance to mechanical stresses, water penetration, and temperature changes. Ensuring even application and proper adhesion at every stage prevents weak spots that could compromise the system's integrity. This multi-layered design provides a seamless and watertight membrane, which is essential for long-term performance. According to the Asphalt Roofing Manufacturers Association, adding layers based on design needs can extend the roof's lifespan significantly, especially in regions prone to temperature fluctuations like Los Angeles.
6. Install the Surfacing Layer
The surfacing layer serves as the roof's protective shield, offering resistance to environmental factors such as ultraviolet rays, physical damage, and water. Common materials used include gravel, mineral granules, or reflective coatings, each tailored to meet specific property needs. Reflective coatings are especially effective in reducing heat absorption, making them ideal for meeting California Title 24 energy standards in Los Angeles. The surfacing layer also plays a role in improving the roof's energy efficiency, reducing cooling costs during hotter months. By protecting the underlying layers, this final step ensures durability and maximizes the roof's performance over time.
7. Inspect the Completed Roof
A comprehensive inspection is crucial to verifying the quality and completeness of the installed built-up roofing system. This step involves checking the surfacing layer for uniform application and ensuring all components meet design specifications. Technicians also assess the roof for gaps, uneven areas, or other defects that could affect its performance. Addressing any detected issues immediately helps avoid future complications and ensures the roof is ready for long-term use. Industry recommendations from the National Roofing Contractors Association emphasize the importance of final inspections to confirm durability and readiness to handle environmental stresses effectively.
How Much Does Built Up Roofing For Commercial Buildings Cost?
Built-up roofing (BUR) for commercial buildings typically costs between $5 and $9 per square foot. This price range depends on factors such as the materials used, the number of layers, and the complexity of the installation. While BUR systems have higher upfront costs than some alternatives, their durability and low maintenance requirements provide excellent long-term value. Investing in a well-installed BUR system can reduce repair expenses and extend the roof's lifespan, making it a cost-effective choice for commercial properties.
| Roofing Type | Cost (Per Square Foot) |
|---|---|
| Built-Up Roofing (BUR) | $5–$9 |
Disclaimer: The costs provided in the table are general estimates and may vary based on factors such as location, materials, labor rates, roof size, and project complexity. For an accurate and detailed quote, consult with a licensed commercial roofing contractor. Prices are subject to change based on market conditions and specific project requirements.