How Effective Is Elastomeric Roofing?

Weather Resistance

• Elastomeric roofing is completely waterproof, which makes it an effective roofing option in terms of weather resistance. Because you can apply it on top of existing roofs, such as bitumen, metal, cement and built-up roofing, elastomeric roofing is a popular choice for remedying leaks. Unlike adding tar to a roof, which is a temporary fix, elastomeric roofing is a permanent weatherizing solution. Apart from being nonporous, a main reason elastomeric roofing is able to maintain its waterproofing capabilities is that it can expand and contract in response to changing weather conditions. During hot summer days, the roofing can stretch, while during cooler periods, the roofing can return to its original size. Unlike other materials, elastomeric roofing does not crack, so it does not present opportunities for leaks to develop.

Energy Efficiency

• On its own, elastomeric roofing is not so effective at increasing the energy efficiency of a home. While applying the roofing requires less petroleum-based substances in comparison to applying other types of roofing, elastomeric roofing is not very reflective. This means that it will attract heat from the sun even during hot summer days when most homeowners are trying to expel heat. However, you can add Energy Star reflective surfaces to the tops of elastomeric roofing to increase energy efficiency. You can also add thermal insulation, which will help trap heat inside during cold weather and help keep heat out during warm weather.

Impact Resistance

• As a flexible, lightweight roofing option, elastomeric roofing does not add significant weight to buildings. This means it does not negatively impact structural integrity and -- as mentioned above -- is an effective option when it comes to adding on to an existing roof. However, the downside to the composition of elastomeric roofing is impact resistance. Unlike with stronger materials, such as metal and cement, large hail from hailstorms can potentially damage elastomeric roofing. For higher impact resistance, you should use high-density roofing substrates and elastomeric coatings or membranes that are at least 90mm -- or about 3.5 inches -- thick.

Vulnerability

• Elastomeric roofing is typically able to adhere well to numerous surface types, even in the face of windy and wet conditions. However, when elastomeric membranes are laid loosely, they have been known to pull away from roofs. To combat this problem, newer elastomeric membranes come with specialized restraint strips for holding down membrane edges. Apart from sometimes pulling away from roofs, elastomeric roofing can be vulnerable to greases, oils and fats. When the roofing absorbs these substances, it can swell up and take on a jell-like consistency. To remedy this issue, you can install grease traps at your roof’s exhaust vents.