Flat roofs are gaining in popularity for a number of reasons. They have a modern look compared with traditional pitched roof designs. A flat roof is also often more energy efficient.
However, there are a number of pros and cons when considering a flat roof design, with one of the major cons being the longevity of the roof type and its materials. Here we’ll explore some of the key flat roof types and their durability.
Reinforced Bitumen Membrane (RBM)
This is the cheapest of the flat roof types in which the roof is gradually built up out of layers of waterproof material, alternated with hot tar, with smooth river stone placed on top. This roof type offers the benefit that it is flame retardant and looks attractive if overlooked from the house. However, it offers a lower durability than other flat roof types.
Similar to the RBM roof type, roof felt is bonded with asphalt in the factory, enabling the roof to be installed in sheets and torched down to bond to the substrate. Again, this is installed in multiple layers with the top layer covered in gravel. This is cheap to install but also offers the same limited durability as the RBM roof type.
Single Ply Membranes
These are made from a variety of materials, though PVC is most common. Single Ply Membranes are installed as a single sheet rather than built up in layers like previous roof systems. This roof system offers increased durability, but comes with a much higher price tag and is generally the most expensive roofing system mentioned in this post.
This roofing system is becoming more popular, largely because of its durability and ease of installation. EDPM sheets are cut to measure from a role and bonded to a substrate. This is usually done with an adhesive which is sometimes ballasted with gravel. All sheets combine to create a single, seamless membrane. This system also offers increased durability over the traditional bitumen based systems; a Firestone EDPM roof installed by the Eco-Roof and Wall company is guaranteed for 25 years. The system also offers reduced environmental impact as well as significantly improving the appearance of your home.