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Ponding Water On Flat Roofs

Contrary to popular belief, a commercial flat roof in Canada can last up to 20 years.

However, they are still subject to wear and tear. If you own or if you're building a commercial building with a flat roof in Calgary, Alberta, there are several important things for you to know. Many owners are not aware of the issues that could arise from not caring for a commercial flat roof.

In order to reduce the amount of time and resources you have to spend repairing your roof, continue reading. This article will tell you everything you need to know about caring for your commercial flat roof.

Pooling Water

One of the most common issues is pooling water. If the flat roof doesn't have proper drainage, water will pool and become stagnant and can cause significant problems.

If you ignore this issue, your commercial roof will likely start to sag. After a heavy rainstorm, it's normal for water to drain off slowly. However, if the water is still there after 48 hours, it's imperative that you contact a professional roofer.


It doesn't matter how durable a roofing material is; eventually, it will experience some weathering. The more exposure a roof has, the higher the chance of problems.

A flat roof is constantly exposed to the sun and other harsh weather, such as hail, strong wind, and lightning strikes. There isn't much you can do to prevent damage due to weather, so it's important that you check it periodically for damages.


Another common problem is debris build-up. Your commercial flat roof will likely have some type of debris at all times, whether it be leaves, trash, or branches. It only becomes an issue when your drains become clogged and block water from draining properly.

Bacteria and Mould Growth

Mould and other bacteria growth are other flat roof issues that will need to be addressed right away. This problem is linked directly to water and moisture buildup.

Mould can be dangerous, especially to your health and others working in the building. It can also cause your roof to be less reflective, which will affect the internal temperature of your building.

Poor Maintenance

One of the biggest reasons commercial flat roofs don't last as long as they should is due to lack of maintenance. You likely have lots of tasks on your plate, and it can be easy to let roof maintenance slip your mind.

However, the best thing you can do is make a plan or maintenance routine. It will save you a lot of money and give you peace of mind knowing your building is safe and sturdy.


Replacing a commercial flat roof is a big investment, one you want to last a long time. The best thing you can do is work with a team of experts.

Don't wait to address commercial flat roof issues. Talk to a professional at Flat Roofing Ltd. to schedule a maintenance service.

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