General Roofing Systems Canada installs IKO shingles throughout Canada. Installations are completed in the following cities: Calgary, Red Deer, Edmonton, Fort McMurray, Lloydminster, Saskatoon, Regina, Medicine Hat, Lethbridge, Canmore, Banff, Cranbrook, Kelowna, Vancouver, Whistler, Winnipeg, Toronto and points between. British Columbia. Alberta. Saskatchewan. Manitoba. Ontario.
When completing low slope re-roofing systems it is important to take into consideration the correct election of material that adheres to the local building codes and material manufacturer’s specifications.
Below we have provided a guideline for low slope shingles, roof membranes of flat roofs, and metal roofing.
Low Slope Roofing Shingles
For roofing with a 3/12 pitch regular shingles can usually be installed with 2 ply 15 lb roofing felt paper as underlay ( Be sure to check with your specific building code and the shingle manufacturer).
The General Roofing Systems Canada (GRS) specification for how to install roofing shingles is to never use felt paper. We prefer to use Ice & Water protection on eaves, valleys, and around chimney flashing. In addition to Ice & Water, we also use a synthetic roof underlay such as titanium.
A roof that has a 2/12 – 3/12 slope is more tentative and the risk for leaks increases. Some shingle manufacturers such as IKO with the Cambridge shingle will warranty their shingles on a low slope roof for twelve years. Malarkey shingles will honour a 30 year warranty on low-slope roofing.
A roof that is 2/12 or less in slope should have a “flat roof” or traditional “low slope membrane” installed. We like to see any roof that is less than a 4/12 slope get a low slope membrane that is fully adhered, mechanically fastened, or ballasted.
Low Slope Roof Membranes (Flat Roofing)
Low slope membranes for flat roofing come in a few categories;
- Single Ply Membrane: Single ply membranes come in the form of EPDM (rubber), TPO (Thermal Plastic), or PVC (Poly Vinyl). Single membranes are either fully adhered, mechanically fastened, or ballasted.
Two Ply Membrane: The primary two ply membrane is the SBS Modified Bitumen that can be torched down or cold applied.
Built up Roofing: Built up roofing is another way of describing multi-layer roofing. An example would be the traditional roofs tops that are commonly referred to as tar and gravel roofs or flat-top tar roofs.
New Built up Roofing: More recently, modern technologies have advanced the built up roof and newer built up flat roof systems. They now utilize environmentally friendly products and modifiers vs. the tar or bitumen that has been more commonly used in tar roof systems. The newer versions of built up roof systems are extremely tough and will outlast almost any other roof. They are VOC free, making them perfect sustainable offerings to low slope roof assemblies. Tough Roof is an example of the modern built up roof systems as is the GRS Liquid Rubber Built up Flat Roof (a four layer voc free engineered liquid rubber flat roof with 800% elasticity and contains environmentally friendly synthetic fabric between layers vs. traditional tar felt paper.
Low Slope Metal Roofing
Low slope metal roofing (steel roofing, roof cladding, standing seam metal roofing) has been used for decades. This is primarily used in commercial and industrial roof settings.
With residential buildings, metal roofing is more typically found on steeper roofs. GRS installs several of metal roofing systems to Mountain villages such as Whistler, Squamish, Canmore, Banff, Cranbrook, Fernie, etc. More and more metal panel and metal shingle roof residential installations are growing,yet the greatest volume of metal work being completed is on industrial facilities.
An issue with this type of roofing is that there is no other form of roofing material that expands or contracts as much as the metal roofing does. The seams between the roof panels, the fasteners, roof openings at vents, chimneys, flashings, and skylights are consistently expanding and contracting . Due to this factor metal roofing systems are prone to leaks.
Another issue with the metal roofing systems is condensation. Many roof leaks in homes or businesses are actually not leaky roofs, they in fact a pooling of water in the ceiling due to condensation. It is important to deal with any condensation or leak issue before installing a new metal roof.
We are able to solve the problem of metal roof leaks by installing a premium roof membrane under the metal roof system. We use a premium caulking tape at the seams in addition to using hidden fasteners. Now one effective way to solve the potential of leaks or condensation issues is to torch a SBS modified membrane or spray liquid rubber before putting the metal roof on.
For a commercial roof and industrial metal roof that is leaking, typically we would coat the roof with liquid rubber. By doing this it helps to ensure that the roof will be good for another 10 years or more. Trying to locate metal roof leaks and deal with them in an isolated way can be quite time consuming and unfortunately highly frustrating . For more information Click on the following link to go to our roof coating section of our website.
Until next time,
The Team at GRS
General Roofing Systems Canada (GRS)
24 Hour Emergency Roof Repair: Call +1.877.497.3528 toll-free.
Calgary, Red Deer, Edmonton, Fort McMurray, Lloydminster, Saskatoon, Regina, Medicine Hat, Lethbridge, Canmore, Banff, Cranbrook, Kelowna, Vancouver, Whistler, Winnipeg, Toronto and points between. British Columbia. Alberta. Saskatchewan. Manitoba. Ontario.