Foundation slab in Toronto basement

Water leaking in your basement is at best an annoyance and a cause of worry, and at worst a threat to your home and to the health of you and your family due to the negative effects of persistent water leaks.  If a water leak is left untreated, water damage to you foundation can occur as well as the development of mold in the home.

It’s important to understand that there are many possible causes for water getting into your basement. Unfortunately, here in Toronto, we have ideal conditions for basement water leaks – lots of wet weather, high water tables and aging foundations.

Here are some of the key causes of water entering your basement:

1. Structural cracks

Concrete foundations are not resistant to cracks.  Cracks in the foundation can be caused by soil settling around the foundation or by movement in the house’s walls.  Once a crack in the foundation has formed it can be quite difficult and expensive to fix.  Prolonged water leaks can expand the cracks and deteriorate the foundation over time.

Horizontal crack in Toronto foundation home

Horizontal Crack

2. Where your four walls meet

The outer perimeter of your house is composed of a thick slab of concrete called a footing.  This footing is poured into a wooden form and a little indentation or channel is thus formed.  This is called a keyway.  The foundation walls are then formed perpendicular to the footings, filling this channel, the keyway.  This forms a little mechanism for holding the foundation walls and footings together snugly, with little or no lateral movement.  The problem comes from the fact that you have two distinct structures, and they are not perfectly bound to one another.  This allows seepage of water from the soil.

Similarly, you have the place where your basement’s floor meets the foundation floor.  The small gap here is called the “cove joint”, it is also a vulnerable location for water seepage.

3. Stairways

You may have an old-fashioned hatchway structure, or a standard stairway going into your basement.  In either case, you may experience cracks.  In general, the connection of a stairway to the structure of your home and basement often creates vulnerable spots for water accumulation.  Add it any significant grading or slope and the problem can be made far worse.

window wells are a source of basement water leaks

4. Windows

Like stairways, windows built into your basement walls can be common culprits of water leakage into your home. Window wells that do not have proper drainage can cause pooling around your foundation and cause water to leak into your basement from cracks around your basement window. The issue here is where the water is being directed,  water should always be routed away from any windows and the foundation wall.

5. Defects with gutters and downspouts

Your gutter system can often cause water problems for your basement.  Making sure your downspout is in working order and it has an extension carrying water away for your home is critically important when attempting to keep your basement dry.

clogged rain gutters in toronto

6. Defective Sump Pit/Drain Tile

The sump pit, beneath your basement, is generally fitted with a pump that is meant to transport water to the ground surface outside the foundation wall.  Many things can cause this system to fail, such as poor installation, a poor drain pipe, or a broken connection between the drain pipe and the sump pump.

Sump pump installed in Toronto home

7. Water rising over a low foundation wall

Your home might be situated in a way that causes water to be able to make it over the foundation wall.  Shorter walls, particularly at a place where runoff from some elevation is present, are a big culprit here.
Water leaking into your basement can be an annoying and persistent problem.  It is important to properly identify the source of you water trouble and consult a qualified expert immediately.  A littler water may not seem like a big deal initially, however left untreated a little problem can easily turn into a large problem.

If you live in Toronto or the surrounding GTA and have water or foundation issues with your home, feel free to contact us here for a free in-home estimate and inspection.


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Waterproofing & Foundation Specialists at Nusite Contractors Ltd
As a family-owned waterproofing and foundation repair business with over 30 years of experience in Toronto, we are proud of our work and stand by it with a full warranty. We’re a service company, working for you. We make sure our customers understand the entire building and repair process, and ensure that our work is done properly and made to last.

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