Many commercial roofing clients want to compare types of roofing systems, and usually, clients are curious about single-ply membrane roofing vs. built-up roofing. Which is more affordable? Which lasts the longest? There’s a lot of information on our blog about single-ply membranes, but today we want to spend some time covering built-up roofing.
Built-Up Roofing Systems have been in use in the U.S. for over 100 years. These roof systems are commonly referred to as “tar and gravel” roofs. Built-up systems are installed by alternating layers of asphalt or tar and supporting fabrics directly onto the roof. You can choose the number of layers (or plies) that are installed. The final layer of a built-up roofing system consists of stone or gravel.
Cost: For an average commercial roof, it will usually cost between $5.50 – $8.50 per square foot in materials and labor to install a typical built-up roofing system. This price range can change depending on the materials you choose.
Installation: The first layer can be adhered directly to the roof substrate. If needed, a base sheet can be fastened to the roof to create a flat and safe work space. A built-up roofing system is installed by alternating layers of bitumen and reinforced fabric. Property managers can choose three, four or five ply roofs to meet their needs and budgets.
The last layer is rock or stone, this layer protects the underlying layers from UV rays, extreme heat or cold, and wind damage. A layer of gravel can be added to be more aesthetically appealing.
Advantages: If properly installed and maintained, a commercial built-up roof can last 40 years. There are a few other benefits of built-up roofing systems:
- Seamless and Waterproof – The continuous solid surface does not require joints or seams, removing the most vulnerable area for leaking.
- Reflects UV Rays – provides ultra-violet protection.
- Low- maintenance – Minimal upkeep needed after installation.
Disadvantages: Built-up roofing systems have been around for decades; their longevity can only be obtained if the roof is maintained properly. Here are other disadvantages of built-up roofing systems:
- Time – Slower installation time frame
- Safety – Hazardous fumes and vapors when installing it
- Weight – Adds extra weight to the building structure
- Costs – Installation costs
- UV Rays – Without the gravel top layer, UV rays can break down the membrane quickly
When building or updating the roof of an existing building, it is essential to consider the type of roof you’d like to install. There are many varying types of roofs, but at ShenCorp, Inc., we offer total roofing services and are happy to help in any way we can. Since 1977, ShenCorp has specialized in commercial roofing and commercial protective roof coating services throughout Winchester, VA, Charlottesville, VA, Waynesboro, VA, Richmond, VA, and other parts of the mid-Atlantic region. Give us a call!