SBS modified bitumen roof system has proven successful for 40 years in Quebec. Popular with architects and general contractors for its reliability on the work site and for its aesthetics, this system is mainly used for flat roofs or low slope roofs. The elastomeric membrane is also more and more used to replace asphalt and gravel or shingles on cathedral roofs because it provides a very uniform and continuous sealing and requires only very little maintenance.
- Modified bitumen systems are typically composed of a first sublayer membrane which is mechanically fixed (preferably screwed) or bonded to the support, and a finishing aggregate coated membrane which protects the bitumen against sunlight.
- The laying of the cap sheet is done with a torch, melting its underside with the underlayer to obtain a perfect fusion. It is recommended to use specialized contractors to obtain a uniform and durable result and above all, to avoid any incident. It is a good idea to ask the roofer for proof of insurance to make sure the clause covering working with flames is indeed mentioned.
All our elastomeric membrane welders followed training with Soprema and CCQ
The main advantage of modified bitumen over other membranes is undoubtedly its aesthetics. The granulated finish is available in a limited but still interesting color palette, including reflective white granulated. The granules allow to making modifications or repairs to the membrane and covering up imperfections afterwards.
The reliability of this roofing allows builders to get the membrane installed and keep relative confidence toward other workers that will walk around on the roof. However, installation of a traffic carpet is advised around high traffic areas like air conditioning units, ventilation, access doors, etc.
While requiring very little maintenance, modified bitumen membrane comes with a long-term risk of gradual degranulation, particularly in areas prone to ice formations. Some methods are possible to restore protection and extend the life of the roofing.
Cleaning the drain of a basin-type of roof is common to all types of roofing.
By precaution, it is recommended to inspect the roof regularly, especially during the fall or after extreme weather events.
Product life : between 25 et 40 years.