A Guide to Commercial Roofing
If you're new to commercial roofing, also known as a flat roof, it might be a little overwhelming choosing the right system. Some systems are less expensive than others. Some last longer than others. Some are better in certain situations than others.
So, how do you choose?
This guide gives you a brief overview of the various commercial roofing systems, the advantages and disadvantages of each, the life expectancy of each, and the average cost to install and repair each one.
Below you'll find answers to the following questions:
What is a commercial roof, also know as a flat roof?
How is a commercial roof different from a residential roof?
Why have a flat roof?
How much does a commercial roof cost?
What are the commercial roof material types?
The life expectancy of the various commercial roof material types.
How much does each commercial roofing product weigh?
What are the pros and cons of PVC, TPO and EPDM?
Which flat roof system is best?
What is a commercial roof?
A commercial roof, also known as a flat roof, is not just a roof for a commercial building. Commercial roofs are often differentiated from residential roofs due to the fact that they have to perform different functions. For example, a commercial roof not only has to protect a building from the weather, but also often support heavy equipment such as large air conditioning units. For this reason, commercial roofs are often made differently and use different materials.
Contrary to the name, a flat roof is not actually flat. Flat roofs are called flat because they are significantly less sloped than traditional residential roofs. In other words, they just look flat. If you place a really long level on a flat roof, you'll see that the angle is 10º or less. By comparison, most common roof pitch angles for houses is between 18º and 36º.
Commercial roofs are often significantly larger than residential roofs and creating a highly sloped roof for a large commercial building is impractical from a construction standpoint.
Flat roofs often have to support heavy equipment such as large air conditioning units. It's much easier to install an air conditioning unit on a flat roof than a highly sloped roof.
Commercial buildings are often constructed with flat roofs instead of highly sloped roofs because flat roofs are cheaper to build.
1. As mentioned above, flat roof frameworks and decks are less expensive to build compared to traditional residential high-sloped roof frameworks.
2. If you want your building to have a lower profile. Maybe there's a height limitation in your city or you need your commercial building to stay below power lines.
3. If you need your building to have a lower slope, for example, if you need to install heavy equipment on it.
Who uses a flat roof?
Most of the time, commercial building owners use a flat roof. However, it is not uncommon to have a flat roof on non-commercial buildings. We have installed flat roofs on new garages and home additions.
The cost to install a commercial roof depends upon the insulation and recovery board underneath the membrane.
The cost to replace a commercial roof also depends upon the condition of the existing roof, if the existing insulation and recovery board needs to be replaced, among other things. So, for our price comparison, let's leave all that aside.
Let's assume you have a 2500 square foot commercial building with a flat roof.
To install just the membrane for a commercial roof, here are some averages:
EPDM: $5.50/sf ($15,000)
TPO: $7.00/sf ($16,000)
PVC: $8.50/sf ($20,000)
There are several commercial roofing material types available today. However, here are the ones we offer:
- PVC (polyvinyl chloride)
- TPO (thermoplastic polyolefin)
- EPDM (ethylene propylene diene monomer). Also known as a rubber roof.
A PVC roof can last 20 years or more when installed correctly using today's modern technology. TPO, 25 years. EPDM, 30 years.
When a commercial roof fails, it is often because it wasn't installed properly. When properly installed, the seems are actually stronger than the membrane itself.
What is TPO roofing?
TPO stands for thermoplastic polyolefin. It is the most affordable of the commercial roofing options. It is a reflective roofing membrane made from polyprophylene and ethylene-propylene rubber polymerized together. Read more about TPO roofing.
What are the cons of a TPO roof?
The only disadvantage of a TPO roof is that it's still a relatively new product. Not all TPO roofs are created equal. Some TPO manufacturers are better than others. After extensive research, we've found that Mule Hide, Versigo and Genflex make a great TPO roofing material.
What is EPDM roofing?
EPDM stands for ethylene propylene diene monomer. EPDM is also known in the industry as a rubber roof. It is an extremely durable synthetic rubber roofing membrane most commonly used on low-slope commercial buildings. Learn more about EPDM roofing.
Which flat roof system is best depends upon your needs and your budget.
Most like TPO because it's white and reflects heat. Even more, TPO has fabric embedded within the membrane for added strength.
PVC is good for restaurants because it's resistant to greases and animal fats.
EPDM is cheaper than TPO which is good for savings.
Choose PVC if you own a restaurant as it's resistant to grease and animal fats.
If you want lower utility bills, again choose PVC as it's the most reflective.
Because it's fire resistant, PVC wins, again.
If cost is the determining factor, choose either TPO or EPDM.