Roll roofing for flat roofs is available in rolls that typically vary in width from 6 to 20 feet wide and up to 100 feet long. Most of the roll roofing available is made from a variant of rubber. Roll roofing includes materials like:
Asphalt roll roofing, also known as selvage roofing is commonly used for buildings that have a low-sloped roof pitch in North America. Made like asphalt shingles, an organic fiberglass or felt mat is saturated with asphalt and then faced with a granular stone aggregate. It typically comes in 18 or 36 inch wide rolls. Roll roofing is generally installed as a single ply and there is hardly the need to overlap.
The American composition roofing industry became prominent in the 1840s and it was prospering by the 1880s. Asphalt pressed into roofing materials were packaged as long strips or rolls to be used on flat roofs. Roll roofing emerged in the late 19th century and was a common roofing material by the beginning of the twentieth century. It wasn’t long before it was replaced by asphalt shingles in 1903. This was because asphalt shingles were easy to transport and the materials used for asphalt shingles were available in good supply during World War I.
Roll roofing is suitable for low-pitched flat roofs. Alternatives to roll roofing include:
Metal Roofs:
Standing seam metal roofs can be installed on a low slope that is no less than 1 in 12 (1:12) pitch. Standing seam roofs can be installed over existing built-up roofs with ease. Seams are generally strong and offer protection against water. Metal roofs are energy-efficient, durable and require little maintenance.
Asphalt Composition Shingles:
Asphalt shingles are mainly made using fiberglass or organic felt. These shingles work great for re-roofing and waterproofing applications. Asphalt shingles are widely used for roofs in North America due to their reasonable costs. Asphalt shingles come in small pieces and hence, take longer to install as compared to roll roofing.
Coated Roof Systems:
Coated roof systems work well in prolonging the lifespan of an existing roof system. Roof coatings have become cost-effective alternatives to roof replacements. The coatings can be applied using a brush, roller or sprayed directly on the roofs. Roofs can be coated with foam, solar reflective paint, elastomeric coatings that include Silicone, Butyl, Acrylic and Polyurethane and more.
Roll roofing can offer protection from fire, rain and wind depending on the materials used in the rolled roof as well as the underlayment used. Customers should always use a fire rated roll roofing product. Rolled roofing that uses asphalt offers good protection from fire, water and strong winds. Asphalt products are proven to resist extreme temperatures are manufactured to comply with the Underwriters Laboratories (UL) standards for fire and wind-resistance. Bitumen Polyester membrane rolls also offer good waterproofing. Rolled roofs can also be painted with waterproofing sealants.
A flat roof receives about 1,000 watts of sunlight per square meter in the midday sun. Roll roofing, that is typically black, will absorb most of the energy from the sun, heating the roof as well as building. Any type of roll roofing system can offer solar reflectance. The black membranes can be coated with white paint to make them reflective. A clean, white roof reflects around 85% of the sunlight and can considerably save on energy.
The cost of roll roofing will vary based on materials, location, installation and other factors. On average, rolled roofing materials cost anywhere from $30 to $100 per square. Installation of the rolled roof can cost $1.50 to $3.00 per square foot.