Commercial roofs require their own special roofing material needs. They tend to be flat roofs, meaning that their slope is less than a certain amount, giving the roof the appearance of being flat (although there is an angle to allow the roof to shed rainwater). One popular type of flat roof that can effectively serve most types of commercial buildings is the torch on/modified bitumen roof. Here at Golden West Exteriors, we offer SBS torch on/modified bitumen roofing installation in Edmonton and Alberta. Let’s go over this commercial roofing material and some of the benefits you can reap from it.

What is Modified Bitumen?

In this type of roof, layers of ABS plastic are laid and topped with a polyester and bitumen blended gravel adding system. Huge flame tossing roofing torches are then used to melt the asphalt bitumen and polyester mix onto the ABS plastic, listing them together. The result is a stronger finished product perfect for set or low slope roof applications.

Benefits of Modified Bitumen

The nature of modified bitumen’s mixture of synthetic rubber polymers and asphalt makes for a very flexible roofing solution. You can expect the following from this material:

  • Modified bitumen can resist damage from extreme temperature fluctuations, as well as minor structural shifts from the building it’s placed on, because it is elastic (with a great resistance to brittleness) and can change shape slightly as needed.
  • Modified bitumen roofing is air and water tight. Not only is it great for waterproofing, but it provides great insulation qualities as well, which can help keep a business’ energy costs from running up too high.
  • Modified bitumen gets high rankings in regards to fireplace, wind, and hail ratings.
  • The average life expectancy of a modified bitumen roof is some time between 15 and 20 service years.

Installation Process

Generally, the installation process for modified bitumen will unfold as follows:

  • Before installation, the old roof must be taken off to inspect the substrate, in order to determine whether it is appropriate for the new roof.
  • Any changes to the substrate, ventilation, etc. will need to be made before installation can start.
  • When the substrate and installation is set up appropriately, ABS plastic paper and particle board is laid in preparation for the bitumen and polyester gravel adding system to be applied.
  • Next, the first layer is applied using a roofing torch. The roof will be waterproof just from the application of the first layer alone.
  • A final layer, called the cap, is added after the first layer. This layer is covered in granules used to safeguard the initial coating from UV light.
  • After the basic roofing installation is complete, flashings and other roofing elements are added on to finish the installation.

SBS Modified Bitumen

Modified bitumen can further improved with application modifiers. Here at Golden West Exteriors, we offer SBS, or styrene butadiene styrene, modified bitumen roofing, which improves the effectiveness of the material. SBS modified bitumen material can stretch about six times the length of regular modified bitumen, and is elastic enough to return to its shape afterwards.


Would you like to take advantage of this amazing commercial roofing option? Golden West Exteriors can help with your SBS torch on/modified bitumen roofing installation in Edmonton or Alberta. We also offer a host of other roofing, siding, windows, and other contracting services. We are high qualified contractors, extensively certified, and our job is never finished until you are satisfied. For more information on how our roofing services can benefit you, please do not hesitate to give us a call at your earliest convenience. We’ll be happy to answer any questions that you may have.