Here’s how to measure your basement's risk of flooding, as shown by a furnished basement living room

As climate change creates more severe weather events, many of which result in water damage to Canadians’ homes, some houses are more at risk for flooding than others. According to the Institute for Catastrophic Loss Reduction, these factors — among others — can increase your basement’s risk for flooding:

  1. You live in a region that’s prone to flooding. If your home is in a river delta, floodplain, or a low-lying coastal region, your basement is at a much higher risk of flooding if heavy rain or melting snow causes water levels to rise and flood the surrounding areas.
  2. Your basement has flooded before. If your home has flooded before and you haven’t found or addressed the cause, you’re more likely to experience a flood again.
  3. You pour fats, cooking oils, and grease down the sink. Throwing grease, cooking oils, and other clog-causing materials like bacon fat, coffee grinds, and food waste can cause a sewer backup, which can lead to water damage.
  4. The sewer grates in front of your home are blocked by debris. If your storm sewer grate is blocked by yard waste, leaves, garbage, ice, or snow, excess water will have nowhere to escape and can seep into your home.
  5. You haven’t cleaned your eaves and downspouts recently. Your home’s gutters and downspouts direct rainwater away from your roofline and protect your home’s roof, walls, and foundation from water damage. If leaves and other debris are allowed to collect, they can create clogs and water will overflow, causing water damage.
  6. There are unsealed cracks in your foundation or basement floor. Over time, cracks in your home’s foundation and basement floor can develop as your home settles into the ground, allowing water to find another way into your home.
  7. The soil beside your home isn’t 10 to 15 cm higher than the soil 1.5 metres away from your home. The soil directly beside your foundation wall should be approximately 10 cm to 15 cm higher than the soil 1.5 metres away from the foundation, so that your yard slopes away from your home and water doesn’t have anywhere to accumulate.
  8. You don’t have a backwater valve. A backwater valve stops sewage and water from flowing into your basement if the main sewer system becomes overwhelmed and begins to back up. 
  9. You don’t have a sump-pump. A sump pump pulls water from your basement and pumps it safely away from your home’s foundation. Sump pumps are especially helpful in rural areas and regions prone to flooding, where rainwater and melting snow can’t easily drain into a municipal sewer system.
  10. You don’t have a reverse slope driveway. A reverse slope driveway is one that leads downward from your home to the street below and directs water away from your home.
  11. Your basement windows are close to the ground. If your basement windows are close to ground level, water that’s collected by your home can potentially enter through them. Installing a window well can help — the bottom of the well should be 15 cm below the bottom of the window with a mixture of gravel and sand to allow drainage.

Do you know if your basement is at risk of flooding? According to the Institute for Catastrophic Loss Reduction, these factors can increase the odds of it happening.

Did you know that standard home insurance policies don’t always cover damage caused by water that enters your home from external sources (like heavy rain, sewer backups, overland flooding, or sump pump failures)? Talk to your licensed insurance broker about the best optional policy add-ons to keep you and your family safe.


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