What Causes Ponding Water on Commercial Flat Roofs?

Large commercial roof with water pooling

Ponding water refers to water that has accumulated on a roof for over two days. It’s a common problem with commercial flat roofs due to their low slope. If you have ponding water on your roof, it’s critical that you get this fixed immediately.

In this post, we’ll discuss the causes of ponding water on commercial flat roofs, what issues it can create, and what to do about it. 

Causes of Ponding Water

Ponding water has many causes, including:

  • Poor Design & Installation: Even though they’re called “flat roofs,” they’re not entirely flat. All roofs must be at least slightly pitched to allow for proper drainage. A roof that doesn’t slope slightly toward the drains is often a sign of an improperly installed roof or poor overall building design. An additional cause may arise from improper installation of the connection point between flat and sloped roof pieces.
  • Clogged Drains: Water has nowhere to go if the drains and gutters are clogged. As a result, it’s likely going to sit on the roof, where real damage could occur.
  • Compressed Insulation: Commercial flat roofs usually aren’t designed to be frequently walked on, nor are they designed to hold heavy items. If either occurs, then it could result in various compressions on the roof, resulting in valleys or low spots where water accrues.
  • Structural Problems: Structural issues, which may be caused by buildings settling over time, can alter the roof’s slope and cause water to sit in certain spots.

The good news is that if these causes are identified, they can easily be fixed with commercial flat roof repair or maintenance work.

Why Ponding Water Is a Problem

Damaged Flat roof

Ponding water on a commercial flat roof can lead to a variety of issues. Perhaps the most obvious problem with ponding is a greater likelihood of roof leaks, which can result in costly water damage remediation and roof repairs. A leaking roof may also result in costly business interruption, especially if the roof needs to be restored or replaced. But aside from the obvious issue of leaks and water damage, ponding water can also result in the following issues:

  • Mold, Mildew, & Algae Growth: When excess water sits on a roof for an extended period, it’s not out of the question for the wind to blow dirt and other particles into it. This can result in vegetative growth, which can create excess weight and root growth on the roof.
  • Pests: Bugs, flies, and mosquitoes tend to breed in water. So, if it pools on your roof during the right time of year, it can serve as an ideal habitat for these bugs and become a nuisance for your business. And these bugs may also attract unwanted animals.
  • Ice Dams: Ice dams form in winter when water runoff refreezes near the roofline before it can adequately drain. But they can also form when ponding water prevents water from properly draining. As more snow accumulates, the ice dams are likely to grow larger, which may result in roof damage and leaks.

How to Prevent Ponding Water on a Flat Roof

The best way to prevent ponding water is to ensure your roof is properly installed from the start. If you’re well past that stage, the best solution is to schedule a roof inspection. Being proactive instead of reactive will help you save time, money, and stress.

A professional roofing company can identify low points, slope issues, and other structural problems before they become worse—and they will become worse if you don’t take action. You’ll also want to ensure you have, and continually implement, a roof maintenance plan. Your roof should ideally be inspected annually, especially before the winter months

Contact Summit for Commercial Flat Roof Inspections & Maintenance

If you’ve noticed ponding water on your commercial flat roof, it’s time to get help from a professional roofing company. 

Summit Commercial Roofing is a family-owned and -operated company specializing in commercial flat roofs. We’ve offered reliable repair, installation, and maintenance services to businesses in Southeast Michigan for over 50 years.

Let our team help you—fill out our online form today to request a roofing inspection. 

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Contact Summit Commercial Roofing Today

Summit Commercial Roofing is proud to be an industry leader in commercial flat roofing replacement, repairs, maintenance and installations. Courtesy, integrity, and transparency are a big part of everything that we do. Are you ready to see why we’re one of the best commercial roofing companies in Southeast Michigan? Call (734) 564-0371 or fill out our online form today to request a quote on our commercial roofing services.

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