basement waterproofing

A water soaked carpet can be a real mess. Especially when it’s in your basement and it’s soaked from possibly contaminated sewer water.  Yuk! Every moment you delay, your carpet’s survival is under threat. At the same time, there’s little purpose in trying to do anything while the water’s still coming in. This is definitely no time to be rash. You need a cool head here.  Here in Toronto, between the weather and the age of many of our homes, basement flooding is quite common.  If you do experience a basement flood, and your have carpet down there, here are a few tips for you to follow.

flooded carpet with mold

Turn off the Water Supply – If a basement suddenly develops a leak, it’s quite possible an appliance down there has developed one too. Turn off the water at the entry point. Just don’t go below because it might not be safe to do so yet.

Switch off the Electricity – Don’t mess with this one. Your life could be at stake. Turning off the main switch is only good enough if the basement’s correctly wired. Rather ask an electrician to make your basement electrically safe for you.

Inspect the Area – Now you can take a good look around the basement, and hopefully find the root cause of the problem. Check the ceiling and the walls for obvious signs of running water. Look at every plumbed-in appliance carefully. Then examine the carpet for water-intrusion from beneath. The darkest, wettest spot is likely where your problem lies.

Salvage the Carpet

If the carpet is cheap, or clearly ruined, don’t waste your time with it. Put in an insurance claim and have a new one fitted. A carpet that isn’t cleaned and dried properly is a great candidate for mold.  However if you have a high insurance excess and consider it worth salvaging, here are two alternative solutions.

  • If the carpet is recoverable but really water-sodden (or you need to uplift it anyway to attend to an underground leak) clear the basement and use a commercial wet-vac to mop up as much water as possible. Then remove the carpet (watch out for rusty nails on edging strips) and take it someplace where it can dry out in the sun.


After that, you can find a carpet fitter to relay it for you. Don’t waste time trying to salvage the underlay though. It’s relatively cheap, and will stretch and tear as you take it up in any case.


  • If the water spill is localized and clearly not welling up from below, all you may need to do is mop it with the commercial wet-vac (don’t press down hard) and then turn on several large fans plus a powerful dehumidifier. Don’t rush things. When it’s finally dry, you can shampoo it clean.

Move Quickly

Ignore a damp carpet in a basement, and you’re inviting mold to settle down there, from where it could gradually migrate upstairs and affect your family’s bronchial health. Should you be unable to take any of the steps we recommend immediately, then it’s time to call in a commercial carpet cleaning service urgently.

Longer-Term Concerns

Clearly, there’s little point in reinstating a carpet until the root cause of the flooding has been solved. Depending on your skills you may be able to sort out a plumbing problem yourself. However, if you’re faced with water intrusion you’re going to need advice from a basement water-proofing specialist, because that’s probably a more serious concern that will require a professional inspection.



wet basements richmond hillOh dear. It’s winter, and the wet basement smells damp again! In fact, it’s getting to the point where you don’t want to go down there any more – but you have to, in order to check the furnace and clean up some of those water leaks from time to time. Here in Toronto, many of the older homes suffer from chronic wet basements and it’s not only annoying, but removes a whole level of a home that could be a perfectly good living space.

While some basement water problems are beyond a homeowners control, like rising water tables and hydrostatic water pressure on the foundation, there are several things you can do to try and keep your basement as dry as possible.

Let’s Take a Walk Outside First

Basements get wet due to rainwater intruding through the ground around them, especially when gutters and downpipes discharge large quantities in a small area. Inspect your water drainage system all the way to the discharge gullies. If the water is pooling above or near your basement, you can bet your last dollar its filtering further down too.

About the Window Wells …

Do you find water pooling under or running down nearby a basement window? Well then, you’re probably looking directly at the problem. Digging out and replacing an old window well can be quiet a mission. But you could probably make the problem disappear by attaching a plastic bubble for less than $50, excluding labor, sealant and a few screws.

Not Solved Yet? Let’s “Crack” the Problem

Water is a mighty curious thing. When it spots a crack in a basement wall from outside, it’s just has to pay a visit to see the view from within. If the cracks are less than two millimeters wide you could have a go with silicone – or hydraulic cement if the gap is bigger. Just make sure you rake out everything that’s loose, and do the job when the gap is dry and dust-free too.  This can be a tricky fix, if it looks like anything other than a hairline crack, you may want to call a basement waterproofing contractor to come and seal it properly.

On to More Serious Matters

It can happen that the integrity of your basement wall has failed in places, and that the water’s permeating directly through it. The correct solution is to expose it on the outside, and water-proof it properly so the problem goes away. If you’re between jobs (or a little cash-strapped maybe) you could apply a sealant on the inside. Rest assured though, the problem will return.

Finishing Off the Job

After you’ve stopped the water penetrating (at least for now) you need to get rid of the remaining moisture, unless you like musty smells and mould. Your sure-fired winner is a heavy duty energy-rated dehumidifier. But don’t go cheap, or you’ll soon be buying another one.

Still Not Fixed?

If your wet basement problem won’t go away (or soon returns) you need to face up to the fact that it’s beyond your scope of work and time. There are a variety of options ranging from weeping tiles to sump pumps. The work is technically advanced. It’s time to call in a basement waterproofing expert to ensure a long term fix to your water problems.


Use foil to find source of leak basement torontoIt’s easy to know a basement’s leaking when there’s water running down the walls, or pooling on the floor. It can be more difficult to find the source of the problem though. As a waterproofing contractor in Toronto, we are often called in to find the source of a basement leak after the homeowner has tried unsuccessfully to find the source.  The following advice is pitched at the level of the novice, or DIY family handyman. Anything more than that and you’re better off to call in a professional waterproofing contractor, before the inconvenience turns to permanent damage.

  1. Check the Ceiling First – If you spot any ceiling stains this must be where you look first – before you blame the walls for water running down them (or the floor because of pooling water). There is no substitute for a comprehensive inspection. If there’s a false ceiling under the concrete slab or rafters, you must remove this in its entirety so you can look properly.


  1. Inspect the Plumbing – Water has an amazing ability to travel almost anywhere because it’s so slippery. In fact it’s even been known to travel uphill for a short distance because of capillary action. Check every joint on your plumbing and appliances thoroughly. Be aware that metal failure does eventually follow on from vibration.


  1. Spot the Efflorescence – Don’t stress, this is just the white power that results from interaction between water, and bricks or concrete. Brush away the powder (it’s harmless although you might like to wear protection), then tape a piece of cooking-foil across the centre of the area. Remove the foil a day later and examine it. If there’s moisture where it pressed against the wall you’ve got a basement leak. If not, the efflorescence is caused by humidity in the air.


  1. Look for Wall Cracks – Where these exist (and there’s water seeping through them) you’ll generally spot them easily because liquid follows gravity, and runs straight down a smooth wall. If not, abandon your cursory search and divide the area into an imaginary grid. Start by looking at the top, then work your way down progressively to the floor.


  1. Check for Peeling Paint – The hydrostatic pressure of water weeping through a wall is powerful enough to lift the paint off. While you’re inspecting for cracks, also check for any sign of mould, because this will only grow where a wall is damp.


  1. Finally, Examine the Floor – If you can’t find a leaky ceiling or damp walls, then the water laying on the floor is welling through it on account of hydrostatic pressure from below. Tell-tale clues of the location of this include lifting floor tiles or a squelchy floor covering. If there’s anything standing on the spot that’s made of metal, it will have started rusting too.

What to do About It?

Now that you’ve found the source of the water leak, your next step should be to do something about it. That’s because over time, water seeping through a building degrades the structure permanently. Before you attempt to fix a leak at the point that it appears, remember that the only way to do this properly is at the source. And if that source is on the outside of a buried basement wall, you may be just a little way out of your depth.  A qualified waterproofing contractor can conduct an inspection, and lay out several possible solutions for you to examine.



scarborough waterprrofingThe short answer is sometimes, but in many cases, no.

Nusite has been in the waterproofing business in Toronto for a long time, I can’t remember how many failed interior basement waterproofing jobs I’ve been asked to fix, and how much money has been wasted in that way (although I’m sure it’s a big number in both cases). It’s not that the work itself was bad, it was just the wrong solution to applied to the job.  The truth is that the only sure-fire way to plug a leak is at its source, and that’s the honest truth.

However there are a few methods that could help you manage the problem from the inside. I’ll tell you about them on the basis that there’s always a reason why something seems inexpensive – but often isn’t in the long run.

Things that Might Work

The correct way to waterproof a basement is from the outside. The logic is the same as putting a roof on top of a house, as opposed to trying to waterproof the ceilings from underneath. Why’s that? The pressure of the water pooling on the ceiling boards will work its way through them, and dislodge the paint from inside. We call that hydrostatic pressure in the water-proofing industry

However even a basement that’s well waterproofed from the outside will still leak if cracks develop in the walls or floor. The same can happen if a plumber drills a hole through through the wall. In that case it’s perfectly feasible to seal the gaps with a polyurethane caulk – or epoxy filler if the openings are wider than one eighth inch.

If the moisture is permeating through the fabric of the building itself, no amount of epoxy or polyurethane (or any other product in my experience) is going to do much good for any length of time. That’s because of hydrostatic pressure, once again.

True, you could install a weeping tile around the internal perimeter of the basement and pump the accumulated water away with an automated sump pump. You could even cover everything nicely with a plastic sheet or panel. But you still haven’t waterproofed your basement.

Toronto waterproofing contractor exterior dig

What Should Work

Concrete, cement and bricks are made from natural products found in the earth. And water seeps through earth in no time at all. The only way to stop it leaching through your basement walls and floors is to prevent it from getting there in the first place. This implies four necessary steps:

  • Lay down a waterproof membrane before you cast the foundations and the floor.


  • Water-proof the outside of the foundations and the walls as they go up.


  • Install an external weeping tile system to lead any ground moisture away.


  • Manage your surrounding home and garden so that rainwater flows away.
installing exterior weeping tile in Toronto home

What Definitely Doesn’t Work

I’ve also seen a great many of the things that should work fail, especially when they’re performed by someone who doesn’t have alot of experience with foundation waterproofing.

The Best Advice of All

If you have a chronic leaky basement, and there doesn’t seem to be an obvious solution.  Have a waterproofing contractor come in and give an inspection.  A good waterproofing company will bring in the necessary tools to find the real source of the leak and can give you an accurate estimate of what it will take to repair the problem.  That doesn’t mean you have to do it, but you will know whether or not it’s a waste of time trying to stop the leak from the interior of your basement.


water leaking through basement floor

Water Leaking Through Basement Floor

While you shouldn’t rule out a home with a wet basement, you do need to do some further investigation before going ahead with a purchase agreement.  Here at Nusite, we’ve been a part of hundreds of home inspections in Toronto over the years.  Many times we get called in when a home inspector or buyers agent discovers a potential problem and recommends a waterproofing contractor come in a give an assessment.

Since basements are basically a hole in  the ground, kind of like an inground swimming pool, and rainwater will naturally flow to low lying areas, basements are bound to have some sort of water problems. Sometimes the seller of the home you buy may not even know of them. At other times, they may try and conceal them. At best you have a repair job ahead of you. At worst, you could be in a legal battle trying to recoup the cost of repairing your basement.

Along with seeking the advice of a  traditional home inspector, if you suspect water problems in the basement, your safest bet is to have a waterproofing contractor inspect the basement before you buy the house. After all, you wouldn’t purchase a second-hand car without asking an expert for an opinion, and having the vehicle tested too. It makes sense to apply the same logic when buying a second-hand home. The waterproofer’s report shouldn’t cost you an arm or a leg either, but could potentially save you from tens of thousands of dollars in home repairs.

Things to Look Out For

Insist on doing the inspection without the seller or their agent hovering nearby.  Alarm bells should start ringing in your head the moment you spot any of the following:

  •  The characteristic musty smell of damp or mould. If you find it in a basement, there’s bound to be moisture down there somewhere too.
  •   Water staining anywhere on the ceiling, floor and walls. Make sure you bottom out on the cause, and find out if it’s still happening.
  •   The white powder the experts call efflorescence. Water leaves this behind over a period of time after it evaporates.
  •   Plaster rendering coming away because of spalding happening inside the wall itself.
  •   Black, brown, green or yellow mould that needs a damp environment in which to take root and multiply.

Things that You Could Attempt Yourself

Sometimes the cause of basement damp is a leaking water pipe or a faulty appliance. If it’s a transient problem like that and you’re a handy person, you may just need to tighten up a joint or two. In other words, the basement is not the problem – it’s the way it’s being used.

The solution can also be as simple as redirecting rainwater where it’s discharging from a gutter, adjusting a garden sprinkler system, or unblocking the drain in a window well. Again, here the basement is quite sound. But no basement will perform well if there’s water dammed up around it.

More Serious Problems

If the above issues are not present, and there’s moisture penetrating through the basement walls from outside, then you have a real problem. Either the drainage systems that were put in place have failed, or they were inadequate in the first place. It’s pointless even trying to stem the flow of water with a cheap kit from a hardware store. You’ll most likely need a professional to assess the situation.

Avoiding All of This

We alluded earlier to the wisdom of arranging a proper survey before bidding for a home that includes a basement. Why take chances with your biggest investment? Obtain peace of mind. Have it checked out first by a certified waterproofing contractor. Know what’s on offer before you buy.