Throughout many communities and business districts in Vancouver, WA, and Portland OR, there are buildings and homes that have a flat roof. This type of roof is gaining popularity because it has great qualities.

If you’re looking for a practical way to upgrade a house or commercial building, a flat roof for your commercial building is worth considering. However, before you make your final decision, you may want to check out the information about flat roofing systems in this guide.

man working on a flat roof in portland oregon

What is a Flat Roof

A flat roof isn’t entirely flat as it has a slight angle. On most building and homes, the slope or pitch is about 1.5 degrees. There are many flat roofing systems that have this type of pitch. The top options include

  • Bur roofing: Built-up roofing systems have a low slope and multiple layers. Bur material is great for harsh climates because the top layer is made of aggregate.
  • Modified bitumen roofing: This material can handle extremely high and low temperatures. Harsh conditions can’t break down modified bitumen roofing since it’s made of asphalt.
  • EPDM roofing: An EPDM roof is used on many buildings throughout the United States because it’s very durable. EPDM roofing is made of propylene and ethylene; however, its membrane is constructed out of a synthetic rubber.
  • Foam roofing: Among all of the flat roof designs, a flat foam roof is the only option that doesn’t have seams. During installations, the foam on this roofing system bonds to edging, vents, and pipes.
  • PVC and TPO roofing: PVC and TPO roofing supplies perform well in rainy climates because their thermoplastic core is leak-resistant. Both roofing options have welded membranes, so water doesn’t seep through their foundation easily.

The Advantages of Flat Roofs

If you’re scouting flat roofing systems, there are several great reasons why you may want to make the investment. Some of the advantages are practical, and others provide financial benefits down the road.

Flat roofs and pitched roofs have different installation costs. The most cost-effective option is a flat roof as it’s cheaper to add a flat roofing system on a home or building.

On average, if you try to install a pitch roof instead of a flat roof, your final bill will increase by over 50 percent. If you buy and install a flat roof, you’ll save thousands of dollars.

A flat roof is a great place to set up an HVAC equipment. On the ground, heating and cooling equipment is at risk as someone could steal parts or vandalize housing components. There is enough space for a large HVAC system on a flat roof, and a technician can access the equipment easily during maintenance and repair situations by riding an elevator to the rooftop.

However, because all flat roofing systems have a different weight capacity, you’ll benefit from consulting a roofing contractor before you buy a new HVAC system for a flat roof. A contractor will inspect the roof’s substructure in order to determine whether or not the foundation can support a commercial HVAC unit.

Never cut corners during an installation job for a commercial HVAC system because puddling will occur around low spots on a flat roof if the HVAC equipment isn’t installed properly.

One of the best advantages is the fast installation time. Because a flat roof has less materials, contractors are able to set up everything quicker. For business owners, this is very convenient because rapid services prevents costly interruptions during the installation process.

This means that all employees can focus on their projects throughout the installation, and if everyone has to step out of the building for safety reasons, the break will only last for hours instead of days. Pitch roofing installations aren’t as convenient because a lot of preparation and work is needed to mount traditional shingles on a roof.

Anyone who wants to help the environment and save money needs a flat roof since it’s the best place to install solar panels. The process of gathering solar energy using solar panels on a sunny day isn’t always easy. If certain panels don’t have a great angle, sunlight won’t shine on the chambers that harvest solar energy.

On a flat roof, you can adjust solar panels conveniently in order to aligned them with the sun. Pitched roofing keep panels locked at a certain angle, which isn’t beneficial when the sun doesn’t shine directly on a roof.

Solar panel systems work best when they’re optimized according to the climate conditions, and maximum optimization is only possible while adjustable panels are mounted on a flat roof.

The Disadvantages of Flat Roofs

Since flat roofing systems aren’t sloped, they can develop drainage issues following rainstorms. Pitched roofs don’t have drainage problems because rain slides down shingles instead of creating puddles. During a light rainstorm, a flat roof performs well as puddles don’t generate in vulnerable spots.

However, when a community gets constant rainfall for several days, water will linger in multiple zones since it will have no way to escape. These puddles will have to evaporate, and the evaporation process only happens when heat builds over a flat roof on a hot day.

If you want a roofing system that’s appealing and attractive, a flat system isn’t a great option. There are only a few color schemes for flat roofing, and they’re all neutral tones.

You can pick a flat roof that’s gray, white, or black. Pitched roofing has color schemes that are bolder and brighter, and they’re every noticeable from a distance.

Common Problems With Flat Roofs To Watch For

A flat roof is a practical investment for a new or vintage building because it provides options. However, if you install a flat roof without a solid maintenance strategy, you may have to deal with a few common problems, such as

  • Debris buildup: When branches and leaves land on a flat roof, they will stay there until someone implements cleanup procedures. Debris can cause major problems if it lingers on a flat roof throughout the winter because it can hold moisture. For example, a pile of leaves stays soggy on a flat roof following rainstorms. If a pile constantly freezes, thaws, and freezes again, this cycle will gradually break down the roof’s foundation.
  • Alligatoring: Aligatoring is a term that describes a roof after it cracks and develops bubbles. It happens when too much sunlight shines directly on a flat roof. This problem can affect residential and commercial flat roofing systems, and without a treatment, water may begin to leak inside of a home or building.
  • Buckling: Buckling is a condition that occurs when a building or home shifts. When a structure’s foundation tilts, the membrane on a flat roof moves as well. The membrane is constructed out of one continuous slab, so a minor shift can make a flat roof buckle. You can prevent buckling by monitoring your building’s foundation. If you’re going to install a new flat roofing system, you could prevent buckling by letting a licensed contractor install everything properly. When a flat roof is installed improperly, the foundation will buckle before more severe problems occur.
  • Wind currents: Strong winds can cause dramatic damage on a flat roof. Since there is only a single continuous sheet on a flat roof, one powerful wind current can generate major damage, and if multiple gusts occur, an entire flat roofing system may fail.
  • Leaks: If a flat roofing system holds debris, develop cracks and bubbles, and buckles, the foundation will leak. These aren’t the only problems that cause leaks as damaged flashing and improper installation can create leaks as well.

Overall, a flat roof can provide security, shelter, and financial perks. If this type of roof sounds appealing, carefully consider all of the pros and cons. Once you fully understand the advantages and disadvantages, you’ll have no problems picking a roof that suits your needs.