photo of a house with a flat roof

How to prevent standing water on a flat roof

Does your residential, industrial or commercial building have a flat roof? Have you noticed water pooling on the roof several hours after a rainfall?


At René Perron Couvreurs, we specialize in installing, repairing and maintaining flat roofs for customers in Montreal and Laval. Our team understands that standing water is a red flag and must be corrected immediately. Keep reading to find out what causes standing water, the consequences of it and how to prevent it from happening to you.


What causes standing water?

It’s normal for small amounts of water to pool on a flat roof shortly after it rains. As long as the waterproof membrane is in good condition, the roof won’t absorb any moisture. However, if there are large puddles on your roof more than 48 hours after a rainfall, it means that water isn’t draining properly. There are two common reasons why this happens:


  • There’s a clogged drain. Water can’t flow properly if your drains and gutters are clogged with debris like twigs and leaves. Simply remove the blockage to get the water flowing again.
  • The roof has an inadequate slope. Flat roofs must have a slight slope to allow water to run off and drain away during inclement weather. If the slope isn’t steep enough, you must call a professional, like the team at René Perron Couvreurs, to take a look. They’ll be able to correct the slope of your roof for optimal drainage.


Can standing water cause damage?

If you call a professional as soon as you notice standing water on your flat roof, it may only require minor repairs. However, if you don’t promptly correct the issue, you may eventually need to replace your entire roof. Standing water is heavy and can cause significant damage. For example, moisture can seep into the building and compromise its structural integrity.


How to prevent standing water

To prevent water from pooling on your flat roof, you must have it maintained and inspected by a professional at least once a year. They’ll promptly identify and correct minor problems before your roof sustains extensive damage.


Do you live in Montreal or Laval and have a flat roof that needs repair? René Perron Couvreurs has been in the roofing industry for nearly 100 years. You can count on our experienced roofers to provide top-notch service. Contact us to make an appointment or request a free quote.