There’s inevitably water in the ground around a basement, and, because cement-based walls and floors are porous, water will seep through them if it can go nowhere else. This water could be from rain filtering downwards, groundwater seeping horizontally through the strata, or a water table pressing upwards.
Here in Toronto, many basements have chronic water problems and there are several solutions to cure the condition, depending on the type of water problem present. While we usually recommend an exterior approach to waterproofing, sometimes that is not an option. In that situation, installing an interior weeping tile system in your basement can be a safe and proven alternative.
When this water comes up against a basement wall or floor, it applies hydrostatic pressure that can be surprisingly powerful. If it can’t find a way through, it pools against the outside bottom of the basement walls, and gradually saturates the inside surface if there’s nowhere else to go. While an interior weeping tile system will not waterproof your basement, will will effectively manage the water entering your basement and channel it away so you never see it.
The traditional method of preventing this is to install a drainage system along the outside bottom of the basement walls. These days this comprises of a plastic pipe typically 40mm in diameter and with holes punched into it along the length. This is wrapped in a water-permeable sheet to keep the dirt out, and then buried at a gently sloping angle leading to a discharge point.
Unfortunately these “weeping tiles” as they are called (the name’s a reference to past building practice) may become clogged as time passes. When that happens, the ground water switches to “Plan B” – that is, it accumulates until the hydrostatic pressure is high enough to find a way into the basement.
What to Do About the Water
You cannot keep water back from the inside of a basement, at least not permanently. This means you either have to excavate, and replace the failed exterior weeping tiles or you have to allow the water to seep through, and then remove it continuously. Canadian homeowners often view the latter as the better of two evils. That’s okay, as long as you’re not using your basement as a living space.
This is obviously not an ideal solution. In fact we recommend you replace the outside system if all possible. Unfortunately, sometimes accessing the outside perimeter of a basement isn’t possible, that’s when an interior weeping tile system comes into play. Installing an interior weeping tile system isn’t a DIY project, as you can see from the steps below.
STEP 1: Break out a trench all around the room. This needs to be around eighteen inches from the walls, and to bottom out below the footings.
STEP 2: Lay in the weeping tile as we described, cover it with gravel and re-pour the floor
STEP 3: Create a sump at the bottom end of the run of weeping tile, and install an automatic electric sump pump to carry the water away before it overflows. Fit a lid so it looks a tidier.
How It Works
Water always gravitates down to the lowest point. The weeping tiles attract it like a magnet. It’s taken away before it rises to above the footings. The result’s a perfectly dry basement inside, provided you hired a professional who’s registered, and knows what they are doing. While installing an interior weeping tile system is not the ideal solution for a dry basement, it’s great alternative when an exterior system is not available.
If you live in Toronto or the surrounding GTA and have questions about installing an interior weeping tile system, you can contact Nusite waterproofing today. We offer a free in-home estimate and inspection of your basement and will work with you to choose the best waterproofing solution for your home and your budget.