Is your basement as safe from flooding as it could be? “It’s not a case of if but when the basement will be flooded from either exterior or interior water sources,” warns civic engineer John Cochren.
Statistics back up Cochren’s concerns. Last year’s floods in Alberta and Ontario caused unprecedented damage, economic disruption and suffering. The Canadian insurance industry already pays $1.7 billion a year in claims due to water damage1, and a recent report from TD Bank suggests more damage could come our way: “The long-term financial impact of natural catastrophes is estimated to cost Canadians $5 billion per year in 2020, and $21-$43 billion by 2050.”2
Basements are particularly vulnerable due to increasingly frequent extreme weather conditions such as heavy rains, winds and ice storms, as well as plumbing failures in our own homes. “I see firsthand the hardship, frustration and fear owners experience from water damage to their home,” says Cochren.
As homeowners, we’re reactive rather than proactive. We install a battery back-up for our sump pumps after a storm has taken out the power and flooded the basement. We install a backflow preventer after the sewer backs up. We clean out the window wells after water comes through the basement window in March.”
The solution to protecting basement against water damage and mold is prevention: build in features to protect against flooding, anticipate future use of basement areas, and install monitoring devices. With this in mind, Cochren has identified 10 features — 5 items to be installed when constructing the home and the remaining 5 when finishing. These prevention items would markedly improve our ability to keep our basements mould and flood resistant as well as healthy and safe. Here’s a sampling.
When the house is being built
- Install 2 floor drains not just 1, and an extra drain for every 1,000 square feet over 1,500
- Elevate the furnace and hot water tank 2 inches off the floor on a housekeeping pad
- Install a 24” x 36” egress window, required by law if the basement is ever converted to a bedroom
These are some of the improvements builders can do to help make the future transition from utility space to living space safer and less expensive. The cost to implement at the time of construction is 1/10 the cost to install later.
While finishing or renovating
- Use a floodsill to elevate drywall framing and insulation two inches off the floor, and let water flow underneath. “That's the number one problem I see as a foundation specialist,” says Cochren. “Foundation walls are made of unreinforced concrete or masonry, and they'll crack. A hairline crack allows water to leak in over time, where it gets trapped behind a 2x4 plate and promotes the growth of mould behind the wall.”
- Install an impermeable flooring system on the basement floor, such as tile or linoleum. Impermeable flooring combined with floodsills allow for 2 inches of water without costly consequences.
- Install an alarm on the sump pump.
- Have a means to monitor basement relative humidity and a means to control it.
To help homeowners prevent water damage, Cochren has produced a 15-minute video and e-book explaining how to build what he describes as “smart basements” that reduce the risk of water damage. The book includes his 10 feature prevention tips. Find out more.