Unlike sloped roofs with inclines that encourage water to run off of them, flat roofs are more or less horizontal. In order to prevent pooling and allow proper drainage, flat roofs are built on a subtle gradient and covered with unique materials. While a combination of tar and gravel was commonly used to prevent water from penetrating the surface of flat roofs, our cold climate presents particular challenges for flat roofs in Toronto / GTA (Greater Toronto Area). These materials were also susceptible to sagging and, consequently, to permitting pooling.
At Professional roofers we use Flat roofing materials that are composed of a consistent membrane¬ which is better adapted to our climate and less vulnerable to sagging.
Where possible, these membranes are applied as a single sheet, and a number of sealants and adhesives are available to allow bonding multiple sheets and dealing with structures penetrating the roof surface.
Although many architects designed homes with flat roofs as living areas, the membranes that cover them are vulnerable to wear and tear from human traffic. In order to get the most out of your flat roof without damaging the protective membrane, a further layer, such as a deck or patio stones, should be installed. These and other measures, such as inspections conducted semi-annually and after major storms will help to significantly extend the lifetime of your flat roof.