Asphalt shingles are one of the most popular roofing materials in Pennsylvania. In fact, they are used on at least 80% of homes in the country. They're easy to install, inexpensive, and can last up to 20 years, but they require maintenance every few years.
Asphalt shingles are made of asphalt, a type of petroleum product. They're made by mixing sand, gravel, and other ingredients, rolling them out into sheets, and then cutting them into squares with grooves on the top side. These grooves help water run off the roof more easily.