Ultraviolet (UV) radiation is one of the primary causes of roofing wear and tear, regardless of roofing type or material. But how can you protect your roof from UV damage?
How Does UV Affect the Roof?
Sunlight is composed of many types of electromagnetic radiation. What we perceive as visible sunlight is merely a small fraction of it. And others like infrared radiation (what we perceive as solar heat) and UV radiation are invisible. UV radiation breaks down the molecular composition of chemicals. Years of exposure to UV rays is the reason why asphalt shingles become brittle and lose hold on their granules. On single-ply roofing systems, it causes brittleness that results in increased likelihood of tears and punctures. On metal roofs, UV radiation can degrade the factory coating and expose bare metal to corrosion.
Roofing manufacturers incorporate features that can help reduce the damage caused by UV rays. Most types of flat roofing are colored white because its naturally reflective properties help reduce the UV and infrared radiation absorbed by the roof. Certain bitumen or asphalt-based roofing products may have granules or coatings with similarly reflective properties.
Elastomeric Roof Coatings
Reflective roofing materials are more effective at reducing heat absorption. UV rays affect the roof’s surface, which means even the most reflective roofing materials will, at some point, require roof repair from UV damage.
Elastomeric or acrylic roof coatings are designed for application on flat roofing systems. While it, like the aforementioned reflective roofing, is also colored white, there are key differences that make it more effective against UV damage:
It’s durable – Elastomeric coatings become brittle as is generally the case with paints and untreated roofing. Another benefit of this is it helps make the roofing surface less vulnerable to punctures.
It doesn’t fade – Elastomeric coatings do not fade and have minimal discoloration. This means the roofing surface maintains reflectivity for most of its lifetime.
It can be applied on existing roofs – If your roof is in relatively good condition, elastomeric coatings can help extend its service life. This means you won’t have to tear down or replace the old roof to gain the benefit of elastomeric coating. It also creates a seamless layer that helps protect the roof from water intrusion.