The number-one job of flat roofing material is to create a barrier impenetrable to water. Flat roofing doesn’t have the benefit of a steep pitch to roll water away, and water has a habit of finding its way in through the smallest crack or crevice. This means that you want to avoid seams at all costs. There are plenty of watertight options that do just that on the market today.
Built-Up Roofing
The built-up roof, or the BUR, is a traditional, relatively inexpensive option for commercial buildings. Otherwise known as the hot-tar-and-gravel roof, installation consists of layers of membrane felt rolls that are bonded together with hot asphalt. This is usually topped with gravel for added durability, which looks nice when seen from above. These roofs also often have the ability to withstand heavy foot traffic, and you may also have the option of a reflective coating instead of gravel for added energy efficiency. Generally, this roofing system is estimated to last from 15 to 20 years, which is on the higher end of all available roofing materials.
Roof Coating
A spray-on roof offers one of the easiest installation opportunities for commercial roofing systems. It requires little prep work and can be sprayed on over your preexisting roof. Spray applications also ensure a seamless coating, as opposed to membranes. However, this choice can be more costly depending on the type of application you choose.
Modified Bitumen
Modified bitumen is a peel-and-stick material that is installed onto the roof by torching it, or by using a cold adhesive, to fasten materials down as it’s rolled out. This is done in layers. Hot asphalt is sometimes also involved. This is one of the most labor-intensive options, and it is not recommended to install onto occupied buildings, although there are some technologies available that can make this process a little bit easier. Bitumen is coated with a mineral surface that reflects heat and can make your building more energy-efficient. When installed properly, and depending on weather conditions, these types of roofing systems should last anywhere from 10 to 20 years.
PVC Membrane
This is another well-known roofing system due to its impressive durability. It is installed in two phases, beginning with a layer of insulation board that forms a dense barrier keeping conditioned air in and improving energy efficiency.
The PVC membrane is then installed in rows, which are welded at the seams. It is then necessary to mechanically secure the edges. If you choose a white PVC that reflects the sun, it can further reduce your energy costs. Depending on the environment, this type of roofing system typically lasts between 15 to 30 years.
EPDM
Short for ethylene propylene diene monomer, this rubber material resembles that of a tire inner tube. Installing EPDM rubber is essentially like putting a large, rubber sticker onto your roof. It is done this way to avoid any seams. Installation can be tricky; the large rolls are difficult to handle and it is important to avoid air bubbles when sealing it down. EPDM usually lasts from 15 to 30 years, giving you an effective option in comparison to the other materials.
TPO
TPO stands for thermoplastic polyolefin, a single-ply roofing membrane, which are sheets of rubber and other synthetics that can be ballasted, mechanically fastened or chemically adhered to the insulation. By serving as a layer of protection for commercial facilities, this roofing system is generally known for its weathering abilities, as well as its tear and break resistance. Depending on the seasonal weather patterns, these roofing systems can last up to 30 years.
Work With A Professional
Choosing the flat roofing system that works best for your building will depend entirely on your budget, how long you’d like it to last and the type of aesthetics you are aiming for. It may be a good idea to have a local contractor come out and give you an assessment, help narrow down your options and potentially offer helpful design and materials tips. Give us a call at (888) 622-1622 if you need help determining what roofing system is best for your commercial building.