The roof is one of those parts of a home that is often forgotten perhaps because it is out of sight. However, regular maintenance checks are necessary to ensure that you get the most out of your roof. Roof waterproofing is an important roof maintenance practice but it becomes more complicated when dealing with a flat roof. Unlike sloped roofs where water can easily slide off, flat roofs have a very shallow slope hence they tend to collect leaves and other debris that may prevent the roof from removing water from your building’s exterior as required.
Importance of Flat Roof Waterproofing
Standing water is a common issue with flat roofing as rainwater can begin to gather in many places.
Sometimes the roof’s drainage may be blocked by debris or the roof may sag in certain places leading to
pooling of water. Pooling water can eventually damage your roof’s protective membrane if it is left for too long. It is therefore important to clear any debris blocking the drainage or increase the roof’s gradient. A pressure washer can be used to clean the flat roof by removing any moss or algae that can be hard to remove with a brush.
How To Waterproof Your Flat Roof?
The approach you decide to use to waterproof your flat roof will depend of several factors such as the size of the roof, the environment, the type of structure as well as the budget. The three main flat roof waterproofing methods include:
– Using reinforced bitumen membranes
– Liquid waterproofing
– Use of single ply membranes
1. Reinforced Bitumen Membranes (RBM)
Most residential property owners use reinforced bitumen membranes to waterproof their flat roofs. The
the process involves bonding together two to three layers of bitumen that are laid across the full surface of the flat roof. A polyester carrier is then combined with this coating to create a waterproof material. In order to attach this waterproof bitumen membrane to your flat roof, you can pour and roll or pour hot bitumen in front to seal the material to the roof. Cold application method can also be used where a cold adhesive is used to bond the material to the roof. Other methods of attaching the RBM to the roof include using a gas torch and self-adhesive.
2. Liquid Waterproofing
Liquid waterproofing involves using a special type of coating to weatherproof your flat roof. While this type of waterproofing can be used on typically all types of roofing, it is more common on flat roofs. Liquid waterproofing can last for 20 to 40 years depending on the quality of the product, the installation process, and roof maintenance after application. Examples include fiberglass liquid membranes and fleece liquid membranes.
3. Single Ply Membranes
This method is more common in larger commercial buildings and expansive residential properties. These sheets can be installed to fit the entire flat roof if necessary. The most common ways of attaching a single ply membrane to the roof include fastening, ballasting, and adhesion. Plastic fasteners can be screwed through the membrane to attach the sheets to the roof deck. Stone ballast can also be placed on top of the sheets and fastened together so that they remain in place. Adhesion involves the use of polyurethane adhesives to ensure that the single ply membrane and the insulation are secured.
When your roof is exposed to too many outside elements, its decking and insulation will begin to rot and decay thus reducing the lifespan of your roof.