When it comes to flat or low-sloped roofing systems, we compare two popular options built-up roofing vs. modified bitumen. Built-up roofing (BUR) and modified bitumen roofing (MBR) are durable and reliable roofing systems that protect against weather elements. However, there are some critical differences between the two that property owners and contractors should consider when deciding which one to choose for their roofing needs.
This guide compares built-up roofing vs. modified bitumen in detail. Read on!
Built-up roofing
Built-up roofing, or BUR, is a traditional roofing system that has been used for over 100 years. It comprises multiple layers of ply sheets and asphalt, alternating and applied over the roof deck, insulation, and vapor retarder. BUR systems are known for their redundancy, as the multiple layers provide resistance to weather and heavy-duty protection for the building.
One of the benefits of BUR systems is their versatility. They can be installed with various application methods, such as hot-mop, cold-applied, or self-adhered. They can also be customized with different types of ply sheets and surfacing materials to meet the project’s specific needs.
However, BUR systems can be heavy and may require additional support for the building structure. They also require skilled labor for installation and maintenance, which can add to the project’s overall cost.
Modified bitumen roofing
Modified bitumen roofing, or MBR, was introduced in the 1970s as an alternative to traditional BUR systems. MBR is asphalt modified with a polymeric material, such as SBS (styrene-butadiene-styrene) or APP (atactic polypropylene). This modification allows the MBR to have greater flexibility and resistance to weather and water intrusion.
One of the benefits of MBR systems is their ease of installation. They can be installed with various application methods, such as hot-mop, cold-applied, heat-welded, or self-adhered. They are also lightweight and can be used on various building structures.
However, MBR systems may not be as durable as BUR systems, as they typically have fewer layers. They may also be more prone to punctures and tears due to their greater flexibility.
Modified bitumen roofing vs. BUR: A detailed comparison
While modified bitumen roofing (MBR) and built-up roofing (BUR) have unique advantages and disadvantages, there are several key differences that homeowners and contractors use to determine the best fit for their specific needs.
Here is a comparison of modified bitumen roofing vs. BUR:
Built-up roofing vs. modified bitumen: Installation process
MBR can be installed with various application methods, like hot-mop, cold-applied, heat-welded, or self-adhered. The installation process is relatively straightforward, which makes it an attractive option for property owners and contractors.
BUR is a more traditional roofing system that involves multiple layers of ply sheets and asphalt, which are alternated and applied over the roof deck, insulation, and vapor retarder. The installation process is more complex than MBR, typically requiring skilled labor.
Built-up roofing vs. modified bitumen: Maintenance
MBR requires regular maintenance to ensure it continues to provide reliable protection against weather elements. Common maintenance tasks include cleaning debris from the surface of the roof, inspecting and repairing any cracks or punctures, and checking the flashing and drainage systems.
BUR also requires regular maintenance to ensure it remains in good condition. This includes inspecting and repairing any leaks or punctures, replacing damaged ply sheets or surfacing materials, and checking the flashing and drainage systems.
Built-up roofing vs. modified bitumen: Durability
MBR can provide reliable protection against the elements for 10 to 20 years with proper maintenance. The polymeric material used to modify the asphalt makes MBR more resistant to weather and water intrusion than traditional asphalt roofing systems.
BUR can withstand extreme weather conditions and heavy foot traffic for 20 to 30 years. The multiple layers of ply sheets and asphalt provide resistance to water intrusion, making BUR a popular choice for commercial buildings.
Built-up roofing vs. modified bitumen: Cost
MBR is generally less expensive than BUR, as it requires less labor and materials for installation. However, the cost of MBR can vary depending on the specific application method used and the type of polymeric material used to modify the asphalt.
BUR is generally more expensive than MBR due to the additional labor and materials required for installation. However, BUR’s long-term durability and reliability can make it a more cost-effective option over time.
FAQs
Can modified bitumen roofing or built-up roofing be installed on residential homes?
MBR and BUR can be installed on residential homes with flat or low-sloped roofs. However, they are more commonly used in commercial buildings.
Which roofing system is more eco-friendly?
Both MBR and BUR can be made with environmentally friendly materials like recycled content and low VOC (volatile organic compound) materials. The eco-friendliness of each system depends on the specific materials used and the installation process.
Which roofing system is better for high-traffic areas?
Built-up roofing is generally better suited for high-traffic areas due to its durability and redundancy. The multiple layers of ply sheets and asphalt provide protection against heavy foot traffic and potential punctures.
Can modified bitumen roofing or built-up roofing be installed over an existing roof?
Yes, both MBR and BUR can be installed over an existing roof. However, consult a roofing professional to determine if this is the best option for the specific project. It may be necessary to remove the existing roof to ensure proper installation and prevent any issues down the line.
Can modified bitumen roofing or built-up roofing be repaired if it gets damaged?
Yes, MBR and BUR can be repaired if they get damaged. However, the extent of the damage will determine the type of repair needed. It is important to address any issues as soon as possible to prevent further damage and ensure the roofing system’s longevity.
Final thoughts
When comparing modified bitumen roofing vs. BUR have their unique advantages and disadvantages. MBR is generally less expensive and easier to install than BUR, while BUR is known for its durability and resistance to water intrusion.
Ultimately, the choice between the two will depend on the specific needs of the project, as well as the budget and timeline. If you have more questions, contact our roofing professionals to determine which roofing system best fits your needs. Regan Roofing has over 30 years of experience in installing, repairing, and maintaining roofing systems in Oceanside, CA, and the surrounding areas.
