Basements are an almost inevitable target for water. That’s because they’re underground, and there’s almost always moisture somewhere nearby. If you think of an inground swimming pool, that’s what a basement is, except it’s trying to keep the water out instead of in. While a well-built, properly water-proofed basement could remain dry almost indefinitely, many others fail, because the job was not done correctly in the first place.
Reasons for the Problem
There are several causes for wet basements. These can occur simultaneously. For purposes of simplicity we separate them below.
- Ground Water – This either filters down from rainwater accumulating above, or through horizontal strata in the ground. If your basement damp problem worsens in rainy months, this could be a likely cause.
- Backed-Up Sewer Pipes – Many older Canadian homes still have storm water run-offs connected to their sewer lines. If your damp problem traces to an overflowing toilet, then you need to modify your drainage system.
- Leaking Pipes – Some plumbers have a habit of concealing pipes in walls. All pipes have to pass through walls anyway. If your floor stays damp throughout the dry season, then you should call in a plumber to do some tests.
Your problem will most likely be caused by rain water filtering through the earth, and coming up against your basement walls and floor where hydrostatic pressure may be quite intense. If you believe this is the case, your solution depends on a combination of prevention and cure.
Before beginning, first tape a sheet of plastic over your basement floor making sure to seal the edges and any joints. Lift it up two weeks later. If the floor’s still damp the water’s rising through it. If not, the problem could be in your walls and you need to look elsewhere.
There’s little you can do about groundwater travelling horizontally through the ground. You have to deal with it when it arrives. However if it’s filtering down from the surface overhead, then that’s a completely different matter. Investigate the following:
- How effectively is the rainwater discharged from your roof? Is it lead away through channels, or pooling in the vicinity of the basement?
- Does the ground slope steadily away from your home allowing a gentle yet effective runoff?
- Turn off your water supply at the entrance to your property. Does the meter stop when everything’s turned off onside? If not there could be a leak in your supply main that’s filtering underground.
Wait a few weeks after implementing the above solutions, preferably during a dry period to let the ground dry out. If there’s still moisture rising through your basement floor you have two options open to you:
- Remove the surrounding earth and install a weeping tile system that stops the ground water in its tracks.
- Install a french drain just inside the basement walls, and pump the water to the outside where it can trickle away harmlessly
These are hardly jobs for amateurs. The work is onerous, and you need protective gear to avoid infections. Besides, is this really the way you want to spend a month of weekends? Consider using professional basement water proofing company instead. The job is messy. It’s important to get it right first time.