There are many commercial roofing systems available to businesses, but not all of them are created equally. And because there are so many; it can be incredibly overwhelming. To help you make an educated decision for your business, we’re comparing the most common commercial roofing systems plus the pros and cons of each.

What are the Different Types of Commercial Roofs?

There are a dozen or more different types of roofing used for commercial roofs, which are usually “flat” with a low slope between .24/12 to 3/12. There are around six main types, but each has sub-types that vary in installation method or other specifications. Therefore, we will keep it simple and cover the most basic and commonly used types.

Built-Up Roofing (BUR)

commercial roofing systems: BUR roofing

This commercial roofing system is the most common one. It consists of many layers (three or more) of felt paper, asphalt, and gravel to create a long-lasting watertight surface that can be walked on without sinking in — meaning it’s great for commercial roofs with heavy foot traffic. The drawbacks? They can be susceptible to pooling water after years of wear and tear from storms and heavy rains.

Pros of Built-Up Roofing

  • Cost-friendly
  • Low-maintenance
  • Great UV protection
  • Excellent weatherproofing
  • Fire-Resistant

Cons of Built-Up Roofing

  • Susceptible to cracking
  • Water pooling over time (check regularly)
  • Blistering due to water leaks and hot sun creating steam pockets

Modified Bitumen

Modified bitumen is layers of asphalt material that have been “modified” using reinforcing, rubber, or plastic materials that, when heated up, can be super flexible and stretch across the entire surface of the roof. In addition, this material makes for a very tight seal because it can get in tough-to-reach places. Modified bitumen can be applied in many ways, including heat applied or rolled, hot-mopped, mechanically adhered, or include a top layer of either UV reflective material or heavy-duty composite.

Pros of Modified Bitumen

  • Many style options 
  • Temperature resistance (works well in extreme cold or heat)
  • Easy to install
  • High UV Resistance
  • Cold-applied options
  • Recyclable material
  • Energy-efficient

Cons of Modified Bitumen

  • Low fire resistance depending on the type
  • Fragile
  • Low life expectancy (10 to 20 years)

Single Ply Membrane

There are two main types of single-ply membrane: EPDM (Ethylene Propylene Diene Terpolymer) and TPO (Thermoplastic Polyolefin). They are basically rubber and other synthetic materials layered to create a nice, protective layer on your commercial roof after being ballasted or chemically adhered.

Pros of Single-Ply Membrane

  • Proven track record for 40+ years
  • Many options of insulation
  • Super lightweight
  • Easy to install

Cons of Single-Ply Membrane

  • You can’t get around roofing components (vents, boots, chimneys) easily. The rolls must be cut and sealed properly.
  • Can puncture easily. Not great for high-traffic commercial roofs.
  • Susceptible to wear from UV rays unless a reflective coating is installed.

Liquid Applied Membrane

commercial roofing systems: liquid applied membrane

Liquid applied membranes are one of the least used materials for commercial roofing. However, they are incredibly cheap, easy to install, self-flash, and easily repaired or replaced.

Pros of Liquid Applied Membrane

  • Flexible—can get around tons of busy spaces
  • Highly elastic
  • Can be hot or cold-applied
  • No flashing needed—it does it itself

Cons of Liquid Applied Membrane

  • Low permeability
  • Must have a uniform thickness to be effective

Green Roofs

commercial roofing systems: green roof

Green roofs, also called vegetative roofing systems, are less commonly used but are definitely an excellent option for highly populated areas. They can help put more oxygen into the air to offset smog in busy cities (concrete jungles, if you will) and can even be utilized as a usable space on rooftops of office buildings or residential apartment properties. In addition, they are great for water drainage and perfect for reusing rainwater.

Pros of Green Roofs

  • Improve the drainage system of your building
  • Lengthen the roof’s lifespan
  • Better thermal performance (very energy-efficient)
  • Improve local air quality
  • Home for local wildlife (insects, butterflies, birds)
  • Opportunity for gardening or social space
  • Environmentally friendly

Cons of Green Roofs

  • Much more expensive than other roofs
  • Requires regular and substantial maintenance
  • It puts a heavy load on the building structure

Metal Roofing

commercial roofing systems: metal roofing

Lastly, commercial metal roofs are some of the strongest and most impact-resistant roofs you can choose. They have continued to grow in popularity in the residential sector, but metal roofing has been widely used for commercial properties for decades. The robust design has more strength and better aesthetics than the other materials we’ve listed so far.

Pros of Metal Roofing

  • Easy installation
  • Beautiful aesthetic and modern design
  • Fire and rot-resistant
  • Longer lifespan (50 to 75 years)
  • Very energy-efficient
  • Low-maintenance and low maintenance costs

Cons of Metal Roofing

  • Very expensive (but great ROI)
  • It can expand and contract in extreme temperature changes
  • Prone to dents and corrosion over time
  • More complex to repair and replace

Overall, any commercial roofing systems we’ve listed can give your business the roof it deserves. If affordability is what you need, a liquid-applied system can be a quick and easy way to get your flat roof covered in no time. On the other hand, if you want more style and care about looks, a gorgeous metal roof would be a great investment. And if you want a low-maintenance solution, any of the layered roofing types are perfect—just set it and forget it.

No matter what you choose, Gouge Roofing is here to help you get the roof you need. Our highly skilled team can get your commercial roof installed in no time. Just reach out, and we can get the process started!