2420 N 3rd St. Suite B Flagstaff, AZ 86004 – Facebook | Houzz

Many commercial buildings and warehouses have flat roofs, and such a style poses a unique challenge for adequately withstanding rain. Traditional pitched roofing systems use gravity to divert water, though flat buildings can’t enjoy this luxury. Instead, they must depend on better materials that won’t absorb the liquid.

The best materials for flat roofs can endure through decades of Arizona weather—sizzling heat, rain, snow, wind, and extreme temperatures—without excessive repairs.

At Polaris Roofing Systems, we provide top-notch roofing repairs, replacements, and installations in and around Flagstaff, Arizona. Read on as our team explains more about flat buildings’ top roof system options.

If you need help picking the right material for your property, contact us at Polaris Roofing Systems in Flagstaff, AZ, at (928) 699-4840 for a free site assessment.


epdm roofing

Ethylene Propylene Diene Monomer (EPDM) is a synthetic rubber roof material that typically comes in black. The dark color absorbs heat, making this material less suitable for common living areas, such as above your bedroom or kitchen.

EPDM roof membranes last for about 50 years and don’t show dirt or stains as easily as other materials on this list. We usually recommend this material for non-living spaces like a shed, garage, or storage facility.

2. TPO

Thermoplastic polyolefin (TPO) systems are single-ply membrane roofs that usually come in white, allowing you to reflect heat away from your building. The light color shows more dirt and stains, so you may need to pressure wash it more often. TPO roofs last approximately 25 years.

3. PVC

pvc roofing

Polyvinyl chloride (PVC) roofing systems can last as long as 40 years, withstanding hurricane-force winds, fires, hail, and more. PVC roofing is similar to EPDM, though it offers better durability and longevity. The most popular PVC color is white, as it improves energy efficiency and helps cool your building, though you can also purchase the material in gray, rust, or brown if you’re concerned about the appearance.

4. Metal

Flat metal roofs use a standing seam assembly, connecting metal panels with mechanical seams. The intelligent system can contract and expand as air temperatures change, allowing maximum durability.

Most metal roofs can last between 30 and 50 years. The standing seam design may be perfect for your building if you prefer a modern, sleek appearance.

5. Built-up Roofs

Built-up roofs (BURs) layer various materials atop each other, creating a strong system that employees can easily walk on when accessing HVAC units or anything else. The layers typically consist of asphalt, rock, gravel, and tar.

Each layer you add to the roof increases the lifespan by approximately five years. For example, if you create a roof with five layers, it should last around 25 years.

Another benefit of the layered solution is the absence of seams. Most materials on our list require seams between panels, which can crack or separate during different weather conditions. BURs have no seams, so they can easily adjust to temperature changes.

6. Modified Bitumen

modified bitumen

Modified bitumen is a roll-on roofing material made from asphalt-based substances. The final product looks similar to a traditional asphalt shingle roof, though it works better on flat applications. The simple installation process can help you save money, though the material is pricier than others on this list.

Of all the best materials for flat roofs, modified bitumen can be the trickiest to repair. If the system leaks, your roofing contractor might struggle to find the source.

7. Spray Polyurethane Foam

Spray polyurethane foam is one of the most durable options for flat roofs, using an elastomeric coating that boasts extreme strength, energy efficiency, and thermal resistance. Installing the sprayed-on roofing requires ample experience and knowledge. If you find the right contractor, your system can last as long as 50 years.

The long lifespan combined with minimal future repairs makes this option one of the most cost-effective and valuable solutions for flat roofs.

Need Help With Your Flat Roof?

Now that you know the best materials for flat roofs, it’s time to pick one for your commercial building. If you need help deciding, Polaris Roofing Systems can offer recommendations based on your property, budget, and goals.

Call us at (928) 699-4840 for a free inspection and estimate for a new flat roof!

Justin Young

Justin Young

Justin young has been in the construction trade for nearly 25 years, focusing on insurance restoration and roofing. While attending Arizona State he worked in new construction custom homes until the opportunity came to get back into restoration and roofing. Roofing came full circle and Justin was promoted to General Manager of a local roofing company. As that progressed he ventured out on his own to start his own company, Polaris Roofing Systems. He prides himself on being on the cutting edge of roofing materials, applications and roof quality. Justin enjoys spending time with his 2 young children and wife. Justin prides himself, his company and continued growth on the people around him and the integrity for which it stands for.

Call Now