False water table in Toronto basement

False water table in Toronto basementFalse water tables can spell trouble for your basement or crawl space, even when these areas are waterproofed. As a homeowner, it can be frustrating when water keeps seeping into these areas when you thought you were protected.  Here in Toronto, almost all homes have basements and with the weather conditions and underground waterways running through Toronto, water seeping into the basement is a constant issue for Toronto homeowners.

Sometimes homeowners think their home is sitting on a high water table, when in fact their house sits over a false water table created by loose back fill.

How False Water Tables Form

A false water table forms because of the process used to excavate for your home. A hole is dug in hard-packed soil for the foundation. After the foundation is built, soil is “back filled” around the perimeter. This fill is not as compacted as the undisturbed soil beyond the foundation area. As a result, water penetrates where it can enter easily; around your home. When it rains, or when snow melts, the water follows the path of least resistance and flows away from the hard-packed, undisturbed soil towards the looser, more porous back fill.

Diagram image of a false water table in Toronto basement

Water that has accumulated will continue to rise if water is coming in too quickly, or the real water table is full and cannot handle any more water. As water always seeks to level itself out, it presses into all the voids in the soil, under the foundation and in the foundation walls. The water will continue to climb as long as there is more water pouring in and this creates what is known as a false water table. This can happen even if your home is built on high ground as the soil around the foundation collects moisture before it has a chance to run off. In the meantime all this water exerts an incredible pressure on your foundation.

Hydrostatic Pressure

Once the false water table fills up and becomes higher than the floor, your trouble really starts. Hydrostatic pressure is 63.4 pounds per cubic foot and the water presses in all directions to find its own level. Most homeowners are not even aware this is happening until there is a heavy rainfall or large amounts of snow are melting. The area under the foundation may store up to 2500 gallons of water, but when this fills the water has to find a place to go. If your foundation has any cracks or weak areas, the water will find it and enter the lower level of your home.

Basement waterproofing in Toronto diagram of basement leaks

Clearly, leaks caused by a false water table cannot be solved with a commercial patch kit. The force is too strong. Excavation alone will not solve the problem either. You will need a system designed specifically for a false water table. This involves both water control and a method of relieving the enormous pressure that builds up against the foundation. This is definitely one problem that you will want expert help with. Failure to attend to a false water table may result in the erosion of your house’s foundation, leading to additional cracks, more damage and additional costs.

Toronto Waterproofing Experts

Contact the experts at Nusite Group for a free inspection and estimate. We use cutting edge technology to find the true source of the basement water leak, which could save you both time and money. We are industry waterproofing experts and service the entire Greater Toronto Area.

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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.