8 Things to Think About if You’re Underpinning Your Basement

For Home Buyers

I recently finished underpinning my basement, and for those of you that don’t know what that means, it involves digging down and lowering our basement so that we could make what was an unusable space actually usable by adding some extra space to our house.

In our case, we had a very low basement with 5 foot ceilings, so we dug down around 4 feet, which included 1 foot for gravel and the concrete floor. Now that the project is complete, our basement has ceiling heights of about 8 feet, which is a serious improvement.

Are you thinking about underpinning your basement? If so, here are 8 things to think about before you get started:


8: The project is likely much bigger than you think it is:

One thing that really stuck with me is how massive of a construction project underpinning my basement was. The space that was underpinned was only about 600 sqft, but there were up to 6 people working here everyday from 7am sharp until 4pm. Between all of the digging, the waterproofing, the concrete removal, the subpump installation and planning, and the various plumbing work that needed to be done, it turned out to be a much bigger project than I actually thought it would be. When all was said and done, it took 5 weeks for our underpinning project to be completed.


7: Make arrangements for an alternate place to park:

Underpinning involves removing massive amounts of dirt, by conveyor belt, into a bin that will likely need to be in your driveway. So, you should plan to arrange for street parking for the length of the project. I called 411 to ask if we could park on our street, they said yes, and I received a parking ticket the next day anyways as it turned out I wasn’t allowed to. It’s best to just go ahead and arrange for street parking before the project starts to avoid any hassles. Parking permits can get pricey of course, depending on where you live, but if you tell the city your home is under construction, you can get a decreased parking permit, and in my case, it actually turned out to be free.


6: Plan for an increase in your hydro bill:

I don’t know why I didn’t think of this, but I never considered the amount of hydro that would be used as part of the project. With various heavy equipment, like jackhammers, drills, misc power tools, and conveyer belts, plugged in and running from early morning until early evening, you can certainly expect an increase in what you would normally pay.


5: Plan out what goes where:

You’ll want to choose a contractor for finishing the basement, or at very least, you should have an idea of what you think the finished basement layout will be, including where walls will go, what rooms you’ll have, and where the bathroom will be. Before the conctrete floor is poured, the underpinning company will want to know where the plumbing will need to be roughed in, and you’ll want to know what rooms will go where, so it makes sense to plan it out ahead of time if you’re able to.


4: Know that it could go above the estimate

As with any renovation project, there are usually unexpected costs. In our case, we had a water table running under our house, which required more digging, more gravel, and more waterproofing, which raised the cost of our project by almost 10K. In our original estimate, their was a note about 2 things that could go wrong that would raise the cost, and this was one of them, so it’s certainly not anyone’s fault, but it is an unexpected cost to deal with. We also ended up removing our basement staircase to make it level with the new basement, but that was also an unexpected cost that we didn’t think about until we saw the almost finished project. Moral of the story? Have extra money on hand to plan out things that are unexpected or any upgrades that you may want to put in.


3: Think about a kitchen

You may not want to have a kitchen in your basement, but you still might want to get the underpinning company to rough in the plumbing for the kitchen. Why? It might help your future resale value if you’re able to say that the basement has all of the hookups for a kitchen so that someone could put in a basement apartment pretty easily if they wanted to.


2: Choose someone with connections

Do you know how to pick a good engineer to plan out the underpinning and evaluate the structural integrity of your home? Me neither. So, if you’re underpinning your basement, you should go with a company that takes care of choosing someone for you. You’ll still want to check out their references of course, but it’ll save you the hassle of making a decision about something you probably don’t know anything about.

As well, do you want to apply for the city building permits yourself? I don’t want to do that either. So, you may as well go with a company that will take care of filing and closing the permits for you and that makes sure that everything is up to the city code.


1: Lastly, and MOST importantly, choose someone reputable:

When we were looking for underpinning companies, we searched HomeStars first. We found a lot of companies that seemed qualified to do it, and we got estimates from 5 different ones, but in the end, we ended up going with TrueNorth Underpinnning, and we couldn’t be more happy with our choice or the results. Their estimate came in higher than the others, but after speaking with Daniel, the owner, as part of our initial walkthrough, we knew that we were making a good decision. During the process, Daniel repeatedly checked in to see if we had questions, and his crew that worked on our project were really nice, friendly, and always had a smile on their faces, despite doing what looked like absolutely back breaking work in a tough environment. If you’re underpinning your basement, you should at least talk to them, but still be sure to do your research and pick the company that you feel most confident about working with on what is sure to be a big project.


Are you thinking about underpinning your basement? Can you think of anything else people should know if they’re considering underpinning theirs? If so, I’d love to hear about it in the comments below.

Thanks for reading.

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  1. Melissa, I enjoyed your explanation for what underpinning is. It’s sometimes hard to understand other definitions because they use all these technical terms. For people who don’t really know anything about underpinning, this was very educational.

    1. Thanks Zequek! I had my own home underpinned when I wrote the article, so I learned quite a bit about the process and what to expect.

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