Benefits of a Built-up Roofing System
Built-up roofing systems are a favorite choice for facilities with flat or low-slope roofs. There are numerous variations of built-up roofing systems, but understanding the basic format is essential if you want to explore the potential benefits of this type of system. The name actually offers a basic explanation. The system starts with a base layer and is built up with the addition of more and more layers until the desired effect is achieved.
As GAF explains, a built-up roofing system generally starts with a base sheet of rigid roof insulation or cover board, which is installed over the roof decking with mechanical fasteners. This provides a waterproof base and a foundational layer for the system. Next comes a layer of either hot asphalt or a comparable cold adhesive. It’s topped with a reinforcing felt, which is sometimes called plyboard. Alternating layers of asphalt and felt continue the system until the planned number of layers is reached. Then, the system is capped with a mineral-surfaced cap sheet. Alternately, a final layer of asphalt is spread and covered with gravel or slag.
What are the benefits of a built-up roofing system? There are many . . .
Reliability
Built-up roofing systems, or BUR systems, have been in use for more than 100 years. With that kind of time-tested service, you know exactly what you’re getting. In the case of a built-up roof, it’s a highly desirable reputation for reliability. Most systems are rated to last up to 20 years, but some constructions can last up to 40 years.
Redundancy
With so many layers of protection, there’s little fear of failure. Even if an upper layer fails, others are there to pick up the slack and protect the building from water intrusion.
Stability
The multiple layers of a built-up roofing system provide a rigid, stable platform. That’s ideal when you need a roof that multitasks. Whether it’s providing usable living space, serving as a place for vegetable gardens, offering a platform for solar panels, or delivering a base for mechanical systems, a built-up roofing system is stable enough to do the job without suffering damage that might compromise its primary mission.
Repairability
Built-up roofing systems can be fixed. The most common problems are open joints, blisters, waves, and cracks. The process for the repair depends on the severity and location of the damage and the age and condition of the roof. Reaching out to a roofing professional will help you determine the best course for repair.
Energy Efficiency
The multiple layers of a built-up roofing system keep heat conductivity between a building’s interior and exterior extremely low. That helps keep your energy bills low as well. The rigid roof insulation that’s typically used as a base layer for this type of system also contributes to its energy efficiency. As an added bonus, you can opt to add a UV reflective coating to the system’s top layer. As the Asphalt Roofing Manufacturers Association reports, this transforms the roof into a cool roof and can be an effective way to earn LEED points or meet Energy Star program requirements.
Affordability
When it comes to affordability, the built-up roofing system’s competitive cost per year of expected service life makes it tough to beat. While the system may be more expensive to install, it offers amazing reliability while demanding little maintenance. Experts recommend an annual inspection to check for blocked gutters or drains, pitch pockets, and signs of damage so that any problems can be dealt with promptly. If issues are encountered, repairs are generally possible. In fact, this type of system can often be restored by resurfacing the roof with a flood coat of asphalt, white or pigmented elastomeric roof coating, fibered aluminum roof coating, or an asphalt coating with gravel.