Renovation & Design

MIKE HOLMES: Sudden leak reveals crack beneath surface

Postmedia/Cracks in foundation walls must be repaired to prevent future leaks and floods.

When problems start happening in the home, most people want to blame something or someone else. "Oh, it's because no one knows how to do anything anymore." "They used cheap materials." "They didn't do this right."

I've made those criticisms a few times myself. But sometimes the source of the problem isn't a bad contractor, tradesperson or builder -- it might be a little closer to home.

I was working on this job where the homeowners were convinced their basement was flooding because two big custom homes were built on both sides of their house. They had lived in their home for almost 10 years and never had a problem. But after these two homes were built, water started coming into the basement through the foundation and around the windows.

Why would this happen? Think about it. A big home means a big roof. So all the water that would have fallen on the ground is now falling on this one roof, and being drained at a few points on the ground. Depending on how close these points are to the property next door, they can direct more water to their foundation. Now multiply that by two, because the home I was working on had this happening on either side.

The homeowners were ready to blame the builder who built the other two homes. But after taking a look at their foundation and basement windows, I knew the flooding could have been prevented.

For starters, there were no window wells around the basement windows. A properly installed window well, with a weeping tile, will take surface water away from the foundation and down to the weeping tile along the footings. Otherwise, all that water can leak into the window at grade.

Next, this house had a cinder-block foundation. I love cinder block, but it cracks easily. If there's a crack anywhere between the blocks or in the cinder blocks themselves, water will find its way into the basement. This house had a few major cracks.

And there were holes in the actual foundation wall. Whoever finished the basement didn't build a proper two-by-four wall away from the foundation. Instead, it was strapped to the cinder block, which doesn't leave any space for electrical outlets. So anywhere there was an electrical outlet, they made a hole in the cinder block.

If that wasn't enough, the house had an old clay weeping-tile system -- not to mention no gravel around the weepers, just sand. The way those systems used to be built was that the different terracotta pieces would just sit next to each other. If there was a tiny gap between them, sand could (and did) get in.

That sediment builds up over the years and can clog the weeping tile. Once that happens, the weeping tile won't be able to drain as well. Before you know it, you've got water in the basement.

Anyone who has ever had to fix their foundation knows the best repairs happen from the outside. So that's what we did.

We had to excavate the side of the house and grind out the cracks. Then we filled them in with hydraulic cement, which expands as it dries so it seals the area. Then we installed a waterproofing membrane system -- right from the footings to just above grade. It's flexible and will keep the foundation watertight.

Finally, we covered everything with a dimpled membrane product that protects the coating underneath and stops the water from coming in.

This was a 60-year-old house, so it had some wear and tear. But if the right pro had properly addressed that wear and tear, the flooding wouldn't have happened.

Eventually, this house was going to get water coming into the basement, regardless of the other two homes. All it needed was a couple more years and one bad storm. Did the two big homes on either side speed up the process? Yes. But they weren't the cause.

The truth is if the house had been properly maintained -- specifically the foundation -- it wouldn't have flooded. It should have been able to stand up to whatever extra run-off there was. The two custom homes put this home to the test. Unfortunately, it showed all the cracks and weak points in the foundation.

Nothing lasts forever. But building the right way and proper maintenance can help prevent problems and ensure your home stands the test of time.

Catch Mike Holmes in an all-new season of Holmes Makes It Right, Tuesdays at 9 p.m. on HGTV. For more information, visit For more information on home renovations, visit


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