Buildings with flat roofs are notoriously difficult to waterproof. Areas of standing water can easily form on roofs like these, which can eventually lead to problems with leaking. Over the years, many different flat roof waterproofing solutions have been introduced. Learning more about the various options from the professional roofer that are available will make it easier for you to decide which solution is the right choice for your property.
1. EPDM (Ethylene Propylene Diene Monomer) Rubber
EPDM rubber is often the preferred choice for waterproofing flat roofs. This pliable material is not only capable of standing up to UV rays but also can survive extreme weather conditions. When installed correctly, it is practically impenetrable by water, meaning that leaks are unlikely to occur. Thanks to its flexible nature, it can expand and contract with changing temperatures, meaning that it is unlikely to crack or break.
EPDM rubber is available in two different forms. With the first option, it comes in large, thin sheets that are rolled out over the surface of the roof. The seams between the sheets are fully sealed together to prevent leaks from occurring at the areas where they meet. This material is quick and easy to install and can last for many years before it needs to be replaced.
EPDM liquid rubber coatings are also available. These coatings are easy to use since they are simply painted on the surface of the roof. To get the best results, the roof needs to be properly cleaned and prepared before applying the coatings. Any areas where there are existing leaks also need to be properly sealed. Once the preparation is complete, the liquid rubber coating is rolled or painted over the entire surface of the roof. Several coats may need to be applied to reach the proper thickness.
The only downside to EPDM rubber is that it is quite expensive. Even a small roof can cost thousands of dollars to seal or replace with this type of material. For homeowners or business owners on a budget, there are more affordable options available, although they may not be as effective at waterproofing.
2. Elastomeric Coatings
Like liquid EPDM coatings, elastomeric coatings are painted directly on the surface of the roof. They come in a can like house paint. Compared to paint, however, they are extremely thick and durable. When painted onto the surface of the roof, they are capable of filling in small cracks and openings where water could be leaking in. This helps create a waterproof seal against the elements.
Compared to EPDM coatings, elastomeric coatings are far more affordable, costing a fraction of the price. This makes them a good option for anyone who is on a budget.
In terms of waterproofing, however, they are not quite as effective as rubber. This is particularly true for roofs that experience a lot of standing water. Still, applying one of these coatings is better than doing nothing at all when it comes to creating a watertight seal.
3. Modified Bitumen
Modified bitumen is one of the more traditional choices for waterproofing a flat roof. This asphalt-based product comes in the form of a membrane that is rolled out over the surface of the roof.
In the past, it had to be heated up with a torch during the application process. Today, however, it usually can be applied cold, which not only makes installation easier but also improves safety. While it does do a good job of waterproofing, it is not as durable as some of the other roofing materials. Additionally, it is black, which can absorb the heat of the sun, making the building much hotter.