Updated: Dec 25, 2022
This article discusses the various types of low slope roofing materials used in the commercial industry. The choice of material depends on factors such as budget, timeline, and value considerations. If you would like to determine the best material for your project, you can schedule a free quote.
TPO or thermoplastic polyolefin is a popular form of single-ply roofing. It takes up about 40% of the commercial roofing market share. TPO comes in a variety of thicknesses ranging from 4 mils to 80 mils. Generally, the thicker the material the more durable it is. TPO is considered more eco-friendly than other forms of membrane roofing due to the absence of plasticizer additives.
TPO roofing is a popular choice in the commercial industry due to its good performance, ease of installation, and energy-efficient properties. It is also resistant to UV, ozone, and chemical exposure, making it a reliable choice for commercial contractors. Its popularity has grown in recent years due to these benefits.
EPDM Roofing Systems
EPDM, or ethylene propylene diene monomer, also known as rubber roofing, is a synthetic rubber used in single-ply roofing systems. Single-ply roofs have fewer seams than asphalt rolled roof systems and do not require torches or hot asphalt for installation. EPDM is an affordable option, and installation is relatively quick and easy, making labor costs low. EPDM roofing solutions can last up to 50 years with proper maintenance, and warranties for EPDM roofing can be as long as 30 years. This type of flat roofing material is readily available and simple to install.
PVC Roofing Systems
PVC, or polyvinyl chloride, is a plastic material commonly used in commercial roofing, also referred to as vinyl roofing. It is a reliable and versatile membrane suitable for all types of single-ply systems. PVC is made from a lower percentage of oil and petroleum compared to TPO and EPDM. A PVC roof consists of a single-ply membrane made up of two layers of PVC material covering a strong, coarse fabric reinforcement. PVC material comes in rolls and can be installed using full adhesion, mechanical fastening, or ballasting and seam welding methods. The top layer is UV-resistant, flexible, and can be colored through pigmentation.
Before plastic and vinyl compounds became widely used, commercial buildings relied on the durability of metal roofing. Metal roofing is sleek, efficient, lightweight, low maintenance, and fire retardant. There are two main types of metal panel roofing: corrugated (roll form) and standing seam (concealed fastener). Metal panels can be made of various metals and alloys, including galvanized steel, aluminum, zinc, tin, copper, and coated or stainless steel. Corrugated metal roofs consist of interlocking rippled sheets, while standing seam metal roofs are made of interlocking panels that run from the ridge to the eave. Corrugated metal sheets are fastened directly to the roof sheathing, while standing seam metal roofs have seams that are raised above the surface. Metal is prone to corrosion, so surface coatings have been developed to protect the material from exposure to temperature, precipitation, and humidity.
MBR or modified bitumen roofing is a flexible coating. The base material is similar to asphalt shingles, but MBR comes in rolled sheets. The sheets are rolled onto the roof atop a base sheet membrane. MBR is lightweight and performs well in colder weather. MBR roofing is often self-adhered for peel-and-stick installation. Over the last 50 years, modified bitumen was greatly improved through the addition of modifiers- atactic polypropylene (APP) and styrene-butaliene-styrene (SBS).
Atactic polypropylene (APP). APP-modified bitumen roofing membrane is typically applied to asphalt with a torch. The contractor spreads the headed membrane across all sections of the roof. The roof's surface can be left smooth or have granules added to it.
Styrene-butaliene-styrene (SBS). SBS modified bitumen roofing is a material made from asphalt and synthetic rubber, making it an exceptionally flexible material for flat roofs. Thanks to its rubber composition, the material is less prone to cracking and sustaining damage from elements like ice and ultraviolet light from the sun.
Built-Up Roofing Systems
BUR, or built-up roofing, is a type of roofing system that consists of alternating layers of reinforcing fabric and asphalt, topped with a layer of aggregate like gravel. BUR systems are one of the oldest waterproofing solutions for flat roofs and are often used on low-slope and flat roofs due to their ability to create a continuous sealed surface. Although the basic system has been around for over a century, BUR roofing products have greatly improved in technology over the years, with many now incorporating a ridge insulation layer for improved energy efficiency.