The real estate market in Toronto is red hot right now. It's a good time to sell investment property, esp residential houses, but not if the domicile has a wet basement. If you want to sell a property in this city for top dollar, it must have a warm dry bottom layer.
After the 2013 record high rainfall levels for spring and summer months, most homes that have a freshly renovated basements now advertise that fact right under the For Sale sign on the front lawn.
Here's a house just north of Danforth and Broadview Ave in east Toronto that's getting waterproofing to cure condensation on the cement in the basement, and a little bit of runoff from the driveway during the spring melt. Its a beautoful home and having a wet basement could kill its market potential.
More details in this Bizcovering piece How a Waterproofing Company Fixes Wet Basement in Toronto From Inside House.
Any kind of moisture can compromise framing, destroy carpeting, and ruin drywall, and make smelly crawl spaces. Some folks only use their basement for storage, but excessive condensation on cement walls can still buckle hardwood flooring above and invite mold and pests.
The cinder blocks had to be drilled individually to puncture the cavities inside which can collect water.
It was through this window that all of the building supply materials were passed...
As you can see just below this window, the driveway is right beside the house, and the homeowner tried to put a bandaid on the problem by caulking the joint with the grey waterproof caulking; this is however little more than decporation, a ribbon of protection against the flash floods. When the ground is soaked from a week of rain, a summer storm can trigger a deluge.
In the case of this home, the driveway and lawn area, with a heavy clay soil, some of the water has nowhere to go. It descends down the fissure at the side of the driveway above the basement region and so approximately 1500 square feet drains into this crevice and if you do that math that much square footage gathers 1,000 gallons of water for every inch of falling rain.
Wet basements flood according to the season in Toronto but for the most part there are five wet months: March, April, May and October, and November.
The standard procedure for drying out a wet basement is to first track down the source of the water. There are three main sources of basement flooding: condensation, run-off, subsurface seepage.
Ask how is the water flooding the basement?
Was the water in basement due to watershed run off? or from seepage (an underground water system which is by far the worst case scenario) or is the moisture due to condensation? Those are the three main ways in which moisture eneters the basement.
In this picture you can see the gravel on top of the special constructed filter hose that surrounds the plastic pipe. There is more about subterreanean landscaping on this Distillery Blog post which documents how waterlogged land can freeze and crack old brick walls in the downtown Toronto historic hotspot.
This homeowner in this case had runoff issues from the driveway above and so elected to have the local waterproofing company come into the home and dig an eight inch trench around the peremiter of the basement walls and then bury a perforated plastic pipe that's wrapped in this white plastic / polymer rubber hose filter. Then its all covered in gravel and finished*
Above this internal gutter to sump pump solution, a plastic membrane covers the wall and overlaps and ends at the gutter that has been dug below the wall.
To remedy all leaks and condensation, the solution would have to be tackled from the inside the house.
This is how you engineer a warm and dry basement.