Definition - What does Roll Roofing mean?
Roll roofing is a material roll used for covering the roofs of buildings that feature low sloped roofs in the Northern regions of the United States, Canada and a few European nations. Commonly used roll roofing material is asphalt roll roofing. This material is the same as that used in asphalt shingles. Roll roofing is an organic or fiberglass mat, asphalt saturated and faced with granular stone aggregate.
One of the reasons for using asphalt-based roll roofing is that asphalt is a good insulator of water and dust. During bad weather it protects the steel building structure from coming in contact with water and becoming corroded.
Corrosionpedia explains Roll Roofing
Roll roofing when compared to asphalt shingles are usually light weight mats and transported in rolls, thus they are often called "asphalt roll roofing." The rolls are commonly 36 inches wide and 33 feet long in size. They are lighter weight compared to asphalt shingles and therefore less expensive. Once the roll roofing is laid on the building structure, it is nailed and fixed by applying an adhesive or lap cement.