As asphalt ages, it becomes brittle. This deterioration is due to a number of factors including, the UV rays from the sun, salt from the roads during the winter months, and oil and gas leaks from vehicles. Sealcoating acts as a barrier against these elements. Studies have shown that when an asphalt sealant is applied from the beginning and continued throughout the life of your pavement, it can greatly increase and even double its lifespan.