Commercial Flat Roofing: The Complete Guide

If you are new to owning or maintaining commercial buildings, learning about commercial flat roofing systems might be helpful. However, you don’t need to be an expert on roofs to know that flat roof systems are expensive to maintain, repair, and replace – and they all eventually leak.

Let’s start our guide by discussing different types of roofing systems, including how long each system typically lasts. We’ll then discuss the factors that shorten the lives of commercial roofs. Finally, we will give you a unique, affordable solution to leaky flat roofs.

Commercial Flat Roofing Systems

Let’s start with an overview of flat roofing materials commonly used in the U.S.

Ethylene Propylene Diene Monomer (EPDM)

EPDM (Ethylene Propylene Diene Monomer) roofing is made with industrial-grade synthetic rubber. This single-ply roofing system is manufactured in rolls. While most EPDM surfaces are black, you can also find them in white, gray, tan, or other colors.

An EPDM system expands and contracts with temperature changes, so it is known for being durable and resilient. Some sources say that an EPDM roofing system can last longer than 30 years – if properly installed and maintained.

However, hail, debris, and foot traffic can damage these flat roofs. Over time, the membrane often begins to separate around parapet walls, seams, and penetrations. The adhesives holding the seams together also dry out and weaken over time, increasing the likelihood of leaks. And aged EPDM roofs often accumulate dirt and contaminants, making them unattractive.

Modified Bitumen

The modified bitumen roofing system is a modern version of the built-up roofing system. It is made of asphalt combined with polymerized rubber or plastic, then reinforced with fiberglass. While the result is a flexible and waterproof membrane, the life expectancy of this type of flat roof system (used with multi-ply roofing material) is only between 10 and 20 years.

A modified bitumen roofing system doesn’t last longer because it tends to hold rainwater or melted snow sooner than other flat roofing materials. Pooling water can cause severe damage to the roof plies and seams.

Metal Roof

Metal panel roofs are probably the oldest type of commercial roofing system. A flat metal roof system is suitable for any type of climate and requires little maintenance. Metal roofing systems are also known for their longevity, as metal roofing can last 30 years or longer.

However, metal roofs do corrode. There are several types of fastening systems, and each wears out over time. Metal roofs also can become dented or punctured on commercial buildings.

TPO Roofs

TPO (thermoplastic polyolefin) roof sheets are a heat-weldable blend of polypropylene and ethylene propylene rubber components. This single-ply roofing system is known for being flexible in colder temperatures. A TPO roof may last between 20-30 years if properly installed and maintained.

However, many TPO roofing systems have failed much sooner than their anticipated lifespan – especially in areas known for excessive heat and ultraviolet light.

PVC Roofs

PVC (polyvinyl chloride) flat roof membranes are excellent choices of commercial roofing materials, as they are waterproof – with the added benefit of being able to withstand harsh chemicals. This type of flat roofing comes in various colors, thicknesses, and widths and has an average life expectancy of up to 30 years.

However, PVC roofs tend to shrink over time, causing seams to pull apart. They also are prone to shattering and punctures during cold weather and have a questionable environmental impact.

Factors that Reduce the Lifespan of a Commercial Roof

You may have noticed that the lifespan range for a flat roof system varies greatly. What factors affect how long your commercial roof will last?

Faulty Installation Process and Poor Materials

Not all commercial roofing contractors are the same. The lifespan of the roof on your commercial building is affected by the quality of the materials and installation process. Unfortunately, some building owners don’t realize their roofing contractor has duped them until just after their warranty expires at the 3 to 5-year mark.

Harsh Climate

Of course, extreme weather conditions, including hail, strong winds, and excess amounts of snow, will reduce the lifespan of your commercial roof. However, sunny days are also hard on roofs, as UV rays accelerate roof deterioration.

leaking commercial flat roof

Poorly Designed Drainage Systems

There are two types of flat roofs: those that leak and those that are about to leak. However, maintaining a proper slope and ensuring that your drainage system works correctly can buy you some time.

Inconsistent Maintenance 

Has the building on the commercial roof been properly maintained? If you are new to the building, you may not know the answer to this question. And even if your roof has been maintained, it will not last forever.

What to Do When Your Flat Roof Starts to Leak

Whether your commercial roof is five, ten, or twenty years old, you have to do something when your flat roof starts leaking. After all, a leaky roof is more than a nuisance – it can also affect the structural integrity of your building and cause a severe health hazard.

Of course, you could have a roofing contractor repair the leaks periodically, but you might feel that that process never ends. And if you have a lot of problems with your flat roof, you might consider replacing it – until you receive a quote and realize you will have to shut down the operation of your building while your roof is being replaced.

commercial flat roofing

If you have a leaky flat roof, reach out to EverSeal, the smarter flat roofing system.

EverSeal is a flat roof sealer that will create a seamless custom roof that will not leak. Even though EverSeal offers a 50-year guarantee, it’s less expensive than flat roof systems that last half as long. In addition, this permanent roof seal system will allow you to save thousands of dollars on commercial flat roof repair and roof replacement costs.

The EverSeal system is applied quietly, in a non-disruptive process that won’t affect your ability to conduct business. The system is all-natural and environmentally friendly. It goes over the top of your existing roof membrane – no matter its condition. The result will be a beautiful, seamless white roof that reflects UV rays, which will help reduce your cooling costs.

Key Takeaways Regarding Flat Roofs

  • There are many different commercial flat roof systems with varying lifespans.
  • While there are some things you can do to extend the life of your commercial roof, all flat roofs eventually leak.
  • Contact EverSeal for an environmentally-friendly, long-term solution if your roof leaks.

Learn More About Flat Roofing Systems For Your Commercial Roof

Are you intrigued with EverSeal’s long-term solution for a leaky flat roof? You should be! Not only will you earn state and local tax benefits from installing our product, but the installation is practically painless. Get an instant satellite quote by visiting EverSeal’s website.

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