Built-up roofing (BUR) systems have long stood as one of the tried-and-true methods for protecting commercial and residential buildings from the elements. Often referred to as “tar and gravel” roofs, BUR systems consist of alternating layers of bitumen and reinforcing fabrics, creating a finished membrane. This multi-layered approach not only offers durability but also provides flexibility in its application.
Roofing Nation recognizes the importance of reliable roofing systems like BUR, and through its platform, we seek to connect homeowners and businesses with trusted professionals who specialize in implementing these enduring roofing solutions. Dive with us into the world of built-up roofing and discover why it remains a favored choice for many homeowners!
Understanding Built-up Roofing Systems
Built-up roofing (BUR) systems, often colloquially referred to as “tar and gravel” roofs, stand as one of the more traditional methods used in roofing, particularly for flat or low-sloped roofs. The name “built-up” is derived from the method’s multi-layered approach, where several layers of reinforcing fabric are alternated with layers of bitumen to create a composite, rubber membrane roofing.
Let’s delve into the nuances of this long-standing roofing method to truly understand its merits and applications.
Components of BUR
- Bitumen: This is the primary adhesive and waterproofing element. Two types of bitumen are used in BUR systems: asphalt (which is heated before application) and coal tar (which remains liquid at ambient temperatures).
- Reinforcing Fabrics: These are often called roofing felts or ply sheets. They provide structural strength to the roofing system. The felts are typically made from glass fiber or organic mats.
- Surfacing Materials: To protect the underlying layers from sunlight and weathering, a top layer, commonly consisting of gravel or crushed stone, is embedded in a top layer of bitumen. Alternative surfacing options include a cap sheet, aluminum coatings, or elastomeric coatings.
Different Types of Built-up Roofs
The heart of a BUR system lies in its multi-layered construction. This approach involves alternating layers of bitumen with reinforcing fabric, culminating in a robust membrane that offers unparalleled protection. The following delves into the different types of built-up roofs:
1. Flat Roof BUR
As the name suggests, this type of BUR system is specifically designed for flat roofs, offering a smooth surface. Flat BURs provide an effective solution for water drainage when installed correctly, mitigating potential pooling or stagnant water. They’re also aesthetically pleasing and offer a sleek appearance, which can be an advantage for certain architectural designs.
2. Layers of Bitumen BUR
This type emphasizes the number and types of bitumen layers used. The two primary modified bitumen roofs are asphalt (which needs to be heated before application) and coal tar (liquid at ambient temperatures). The layers can vary, but most BUR systems involve at least three to five. Multiple layers of modified bitumen roofing systems offer superior waterproofing and durability.
They also provide flexibility, accommodating the building’s natural movements without compromising the integrity of the roof. The choice between asphalt and coal tar often depends on regional preferences and specific performance requirements.
3. Gravel Roofs (Ballasted BUR)
This BUR system features a top layer of gravel or crushed stone embedded in the final bitumen layer. This serves as a protective shield for the layers beneath. Gravel roofs are especially advantageous in areas prone to strong winds as the gravel acts as a ballast, preventing wind uplift.
Additionally, the gravel layer provides an extra barrier against UV rays, which can extend the life of the underlying bitumen. The gravel also imparts a fire-resistant quality to the roof.
Advantages of Installing a Built-Up Roof System
Built-up roofing (BUR) systems have been a staple in the roofing industry for over a century, especially in the realm of commercial roofing solutions. The longevity of its use is a testament to the myriad of advantages it offers. Let’s delve into the significant benefits of installing a BUR system:
1. Superior Protection from Extreme Weather Conditions
BUR systems are characterized by their multiple layers of bitumen and reinforcing fabric. This multi-layered approach acts as a formidable shield against various climatic adversities.
Whetehr it’s scorching sun, pounding rain, or heavy snow, the robust nature of BUR ensures that the building remains protected. It is especially resistant to strong winds and can withstand the rigorous challenges posed by changing seasons.
2. Waterproof Membrane and Hot Asphalt Offering Protection Against Leaks
The layers of bitumen, especially when combined with hot asphalt, form a continuous, impermeable barrier. This watertight membrane ensures that water doesn’t seep through, making BUR systems exceptionally resistant to leaks. This quality is especially advantageous for flat roofing materials where water pooling is a common concern.
3. Long Lifespan and Low Maintenance Requirements
A quality built-up roofing installation is made to last. With a potential lifespan of 20-30 years, or even longer with proper care, BUR systems require minimal maintenance. This longevity translates to fewer disruptions and less frequent roofing replacements, saving both time and money in the long run.
4. Variety of Commercial Building Applications
BUR systems are not a one-size-fits-all solution. Their versatility means they can be tailored by various commercial roofing contractors. Whether it’s a warehouse, an office building, or a retail establishment, BUR can be adapted to fit. Its flexible nature means it can accommodate different roofing options when it comes to sizes, shapes, and specific requirements.
5. Cost-Effective Solutions for Commercial Roofing Systems
While the initial installation cost of BUR systems can be higher than some other roofing methods, its long lifespan and low maintenance needs often result in lower costs over time. For businesses, this means a better return on investment. The reduced frequency of major repairs or replacements can lead to significant savings, making BUR a cost-effective solution for long-term commercial roofing needs.
Built-Up Roof Installation and Repair Services
BUR systems, with their tried-and-true reputation for durability and versatility, are a popular choice for many commercial and residential structures, especially those with flat roofing systems or low-sloped roofs. However, the efficacy of these roofs largely depends on the quality of installation and timely maintenance. Here’s an overview of the installation and roofing repair services for BUR systems.
Installation of Built-Up Roofs
- Site Preparation: Before any installation begins, the existing roof (if any) is usually cleared off, ensuring a clean and smooth surface. This might involve removing old roofing materials, debris, and making sure the deck is in good condition.
- Base Sheet Application: A base sheet is anchored to the roof deck to serve as the foundation for subsequent layers.
- Layering: The core of BUR installation. Multiple layers of bitumen (either asphalt or coal tar) are alternated with reinforcing fabric. Each layer is torched or adhered to ensure complete bonding.
- Top Layer Application: Depending on the specific BUR type, the top layer could be a specialized cap sheet, a layer of gravel, or other protective surfacing materials.
- Final Inspection: Once installed, a thorough inspection is done to ensure all layers are correctly bonded and that there are no imperfections that could lead to future issues.
Built-Up Roof Repair Services
- Regular Inspection: This is paramount. Regular check-ups can identify potential problems like blistering, pooling, or punctures before they exacerbate.
- Blister Repair: Over time, blisters or bubbles can form on BUR systems due to trapped moisture. These can be repaired by cutting out the blistered section and replacing it with new layers of bitumen and fabric.
- Puncture and Tear Repair: Physical damage can be patched using a piece of reinforcing fabric and bitumen, ensuring that the area around the damage is also properly sealed.
- Resurfacing: If a significant part of the roof shows wear but the base layers are intact, a new layer of bitumen and roofing surface material can be applied as a refresh.
- Water Pooling Solutions: If stagnant water is noted, solutions might include installing additional drains, adding tapered insulation to improve slope, or patching low spots.
- Reapplication of Protective Surfacing: The top layer, especially if it’s gravel or a similar material, might get scattered or worn down over time. Reapplying this can extend the roof’s life.
Frequently Asked Questions
1. What is a Built-Up Roofing (BUR) system?
A BUR system is a traditional roofing method for flat or low-sloped roofs, consisting of alternating layers of bitumen and reinforcing fabric. These layers are built up on the roof to form a continuous sealed surface.
2. How long does a BUR system typically last?
With proper installation and maintenance, a BUR system can last anywhere from 20 to 30 years, sometimes even longer.
3. What are the main components of a BUR system?
The primary components include bitumen (either asphalt or coal tar), reinforcing fabrics (often called roofing felts or ply sheets), and a top layer, which can be gravel, a cap sheet, or other protective surfacing materials.
4. Is a BUR system suitable for all types of buildings?
While BUR systems are versatile, they are primarily used for commercial structures with flat roof option or low-sloped roofs. However, they can be adapted for certain residential applications as well.
5. How does a BUR system fare in extreme weather conditions?
Due to its multi-layered construction, BUR systems offer superior protection against various extreme weather conditions, including intense sun, heavy rain, snow, and strong winds.
6. Is the BUR system a costly roofing solution?
While the initial installation might be higher than some other roofing types, the long lifespan and low maintenance needs of a BUR system often result in cost savings over time.
Find Built-Up Roofing Contractors Near You
In the vast realm of roofing solutions, ensuring you have the right system in place is pivotal for the longevity, safety, and cost-effectiveness of your structure. While understanding these systems is crucial, having the right partner to guide you through the decision-making process can make all the difference. Roof Nation, with its commitment to excellence and vast expertise, stands as a beacon for all your roofing needs!
Don’t leave your roofing needs to chance. Join the myriad of satisfied customers who’ve found the perfect roofing company with Roof Nation. Contact Roof Nation today and get in touch with a professional roofing contractor in your area.