Everything You Need to Know about Built Up Roofing, and Why
May 29, 2017
If you’re looking for cost-effective, durable roofing alternative for your commercial property, built up roofing is an option worth considering. Also called “BUR” and “tar and gravel,” this type of low-slope roof has been in use since the 1840s, and its proven reliability is why it’s still one of the most popular roof systems used on commercial buildings.
Built Up Roofing Basics
A built up roof is a fully-adhered membrane that’s custom manufactured on site. It’s composed of alternating layers of roofing felts and hot bitumen that are applied on top of the decking and insulation.
- The bitumen – usually either asphalt or coal tar – saturates the felts and acts as a waterproofing agent and adhesive.
- The reinforcing fiberglass, non-woven synthetic or organic fiber felts provide strength and stability.
Most BUR roofs consist of three or four layers, and are topped with either a cold-applied coating, a bitumen flood coat with gravel, or a mineral-surfaced cap sheet to protect the membrane from UV degradation. A well-constructed BUR can last for 30 years, or more, with proper maintenance. A contractor’s knowledge of BUR systems and quality control during installation directly affect the performance of the finished roof and how long it lasts.
Advantages of Built-Up Roofing for Your St. Louis Commercial Property
There are a number of reasons why built up roofing remains popular with St. Louis property owners:
- Leak protection. With its multiple felt layers sealed by water-resistant bitumen, a BUR roof is less likely to leak. If the top layer is damaged, the layers beneath can still keep water out until repairs are made.
- Cost effectiveness. Not only does a built up roof have a lengthy expected service life compared to other roof systems, but it’s also easily and inexpensively repaired or resurfaced, giving it a low life cycle cost.
- Versatility and durability. A BUR can be installed over most types of decking and insulation, as long a suitable substrate is in place. The finished product is a tough, durable membrane that tolerates foot traffic and resists hail damage, fire and wind uplift.
- Energy efficiency. When insulation is installed beneath its multiple sealed layers, a BUR can provide a higher R-value and superior resistance to heat conduction. A reflective top coat can also be applied for even greater energy efficiency.
Contact us at Jewett Roofing to learn more about built up roofing for your St. Louis commercial property.