Can Excessive Sun Exposure Damage My Roof?

All roofs are outdoors, so they are all exposed to the sun. However, the amount of sun your roof will have to deal with varies greatly by your climate. In California, we have long days of intense sun that does stress our roofing materials. Can this excessive sun damage your roof, and what should you do about it?

Ultraviolet Rays and Asphalt

The sun gives off ultraviolet (UV) rays. There are a few types of UV rays in sunlight. The same kind that burns your sun can degrade asphalt, the primary material in shingles. Asphalt is very resistant to the sun, which is one of the reasons that it makes for excellent roofing material. Manufacturers also place granules on the top of the shingle that both add color and reflect light away from the shingles to give them a longer lifespan.

The sun won’t degrade your shingles for many years under most circumstances. However, it typically what causes the shingles to begin to rip and fall off at the very end of their life cycle. Shingles should be replaced before they get to this point, as they provide very poor protection once they are falling apart.

The Heat from the Sun

The heat from the sun also has secondary effects on your shingles. The heat can bake shingles, evaporating the oil in them, creating a cracked and brittle surface. It can also cause the asphalt to expand, which is fine until cooler weather arrives and the material contracts, making cracks even worse. This is called thermal shock, and it can end your roof’s lifespan early.

Will My Roof Fail Early?

If you live in California, your shingles will not have as long of a lifespan as they would in a colder climate. The excess sun is harsh on them over the years, and they will eventually fail. However, you should still get a decade or more out of your asphalt shingles. The manufacturers’ warranties don’t change with the climate. As long as someone is not intentionally concentrating sunlight on your roof, like with a magnifying glass or from a large glass building nearby, your roof shouldn’t fail earlier than expected because of sun damage.

What Can I Do About Sun Damage to My Roof?

Once your shingles are on your roof, there’s nothing you can do to protect them from the sun. That said, if you’re getting a roof replacement anyway, you can choose a shingle that is better for our intensely sunny climate.

We prefer CertainTeed shingles because of their reputation for quality and we have no qualms about recommending them in our high-heat environment. CertainTeed also carries cool roof shingles that reflect more of the sun’s light and heat. These shingles can help you save money on your utilities and may last longer in high heat conditions. They include: