Tue. May 21st, 2024

Our basement construction involved two major construction pieces: the underpinning and the hydronics work. Since it only required us coordinating with two trades, we decided to coordinate the work ourselves and act as our own general contractor. GCs tend to charge about 25% for their services, so this was also a pretty good incentive to manage the work ourselves.


Our basement construction was set to start on in mid-September and last 6 weeks. We were required to submit a City of Toronto Building Permit, which we did and had approved in time to start the work. Yay! I have more on this permit process below…

The underpinners arrived on September 15 and set themselves up. The first day of construction was really to mobilize, but it wasn’t long before some serious work started and the content of our basement was moved to our front lawn.

We didn’t really know how the underpinning was actually done before they started, but it’s pretty fascinating. The underpinning has to happen in three sections (you can see the spray paint in the photo below). All section 1s are dug first and filled with concrete before moving onto the next. Basically, they first create a new foundation (underpin) before they dig out the rest of the floor.

They dug 3-foot holes and build a mould for the concrete.

Then a big truck comes and fills the holes with concrete.

Once the concrete in the Section 1 is dry, they move onto the next hole and repeat the process.

The concrete dries again and and they move onto the third and final section. Our underpinners actually poured in more than three phases, but there’s nothing structurally wrong with that – it’s just far less efficient and added to the time it took to complete the work.

Then they start digging down the rest of the floor.

Unfortunately our sewer drain was too high and needed to be lowered, which also meant digging up our front lawn.

Since they had everything open anyways, we also decided to upgrade our water pipes to City property to get rid of all that lead!

Once the underpinning was done, they also installed a waterproofing membrane along the walls.

Eventually it was time to put down all the drains. The location of each drain had to be very exact, so we made sure to check each one before the concrete floor was poured (also because they weren’t great at precision work and required the supervision). We made a plan and gave it to our underpinners and really stressed how accurate it needed to be.

They laid the drains in a day or so and, once we confirmed their location, covered them with gravel.

They then installed insulation sheets, which would help keep a barrier between the cold ground and our soon-to-be warm floor.

It was then time to bring in our hydronics guy to lay down the radiant flooring. He only took about half a day to complete the installation. They installed the pipes in three sections to give us three separately controlled areas: one for the main area, one for where the bathroom would be and one for the bedroom. 

Once the radiant flooring was installed, the last thing to do was pour the concrete floor. It was really amazing to see this stage because we were finally nearing the end of this never-ending construction.

It took a few days before we could go into the basement because we wanted to make sure the floor was dry enough that we wouldn’t do any damage. We were anxious to get down there because we needed to install our boiler (we still had no heat in the house) and build our basement stairs.

We hired Luke to build us a new set of stairs for $1000. We were hoping to just extend the stairs, but the underpinners cut them off (leaving about 3 steps at the top) so we essentially needed a brand new set. We had some back and forth with the City about what we should build (since building to code was impossible), and gave Luke the specs. Unfortunately he didn’t really build what we needed (the stairs should have been steeper to get the clearance that the inspector wanted and he built them too short). He also built them too short, so they didn’t reach the ground. We had given him a $500 deposit for materials and said that we’d pay him the rest when he came back. Well, Luke never came back, so my dad had to finish the stairs. At least we saved ourselves $500.


Deficiencies are pretty common on construction jobs and it’s important to take note of everything that isn’t complete or done properly (as well as ensure that the contract requires them to leave your house in the state in started). Once the work was ‘done’, we had them come back to do a deficiency walk-through.

There were a couple of major issues.

The first was that our front garden had been completely destroyed by the construction bin.

So we had them replace the retaining wall. It’s now much nicer and matches our neighbour’s lawn.

During construction, the underpinners removed our basement’s back window so they could move things in and out of the basement. Well, when they finished the work, they realized that they lost the window so we had them replace it with a new one.

The window installation was another example of their fine craftsmanship.

We also had our front walkway sink in because they didn’t compact it enough the first time, so they had to come and redo that as well.

One of the more annoying mistakes was their installation of the water pipe. For some reason they decided to place it a good 4-5 inches away from the wall, which meant that I couldn’t hide the pipe in a future wall.

We had to confirm with our hydronics guy that there were no radiant heat pipes between the water pipe and the wall (which there weren’t) and then had the underpinners come back, cut up the concrete, move the pipe and re-pour.

The biggest issue we had was their overall attention to detail, and this problem was highlighted in their concrete work. They were extremely sloppy in how they finished the concrete. 

The door to access our backwater valve door, which will sit in the middle of our living space (so not hidden at all), wasn’t installed correctly (it’s not level) and looks terrible. Our concrete polisher was able to patch it, but we couldn’t fix the fact that it’s not flush with the floor.

But the worst part of this job that really makes my blood boil is that they completely screwed up the concrete pour. Our vision for the basement was to have beautifully polished concrete floors. It’s why we installed radiant heat, it’s why we chose the layout and design we did, and it’s why we had several conversations with our underpinners about the colour of the concrete and the size of the aggregate they were using. We couldn’t have made it more clear that we really cared about those floors. 

When the floor was poured, it wasn’t even, but we made our peace with that (since nothing in our house is even or level). But we had no idea just how bad the job was until our polishers started polishing the floor.

Concrete Polishing

The final step in our basement renovation was finishing the concrete floors. I was so excited to have beautiful terrazzo-looking concrete floors.

We hired a highly recommended concrete polisher who was fantastic to work with. He quoted us $2,800 for the entire basement (which is steep, but in line with other quotes) and fit us into his busy schedule.

When they started grinding the floor on the first day, he called me to tell me he had some bad news. The grinding uncovered footprints all over the basement floor. I thought he was being a bit dramatic and perhaps there were a few footprints. No. They were everywhere.

Those aren’t dusty footprint spots. Those are embedded in the concrete.

After the concrete is poured, the process of troweling allows the cream from the concrete to rise to the top above the aggregate. Polishing concrete grinds away this top cream coat and reveals the aggregate underneath. This is why we couldn’t see any imperfections – they hadn’t been revealed yet.

When the underpinners walked on the concrete, they actually pushed the aggregate lower in those spots so their footprints didn’t have any aggregate.

I was heartbroken and not really sure what to do. The first thing I did was call our underpinners and demanded that they come to our house to see what had happened. They came, but did not accept responsibility for the problem. According to them, this is how they do every job and they’ve never had a problem. They also claimed that they didn’t walk on the floor and used foam pads to move around. If that had been the case, I would be dealing with large rectangle shapes and not individual footprint marks. They also recommended grinding the concrete down an inch or so to get below the footprints. First of all, you don’t grind an inch of concrete. Second, we have pipes under our floors and there was no way we were risking puncturing the pipes.

Our entire basement looked like someone was dusting for a crime scene. I was so angry.

Luckily our concrete polishers had some ideas. They came back and sanded with a lower grit to create a more matte finish. It worked well but wasn’t perfect.

The 3 day concrete polishing job turned into 6 days and created a tonne more dust than it should have. Considering where we started, the floors looked pretty great when they were done. I’m still angry that I don’t have my beautiful terrazzo-like floor, but I can live with it. Mostly because I have to live with it.

Life During Construction

We lived in the house during all of the construction. I was surprised by how clean the underpinning work was. I mean, the basement was a disaster area, but the crew did a great job cleaning up when they left, so the outside of the house was mostly free of debris. Inside, we covered the furniture to protect it from any dust, but it was a non-issue. The crew was pretty good at covering the floor to protect it from excess sand and dirt, but we had to remind them a few times when they got lazy. 

The biggest challenge, however, was that we didn’t have any heat. Since we were changing from a furnace to a boiler, we covered all of our floor vents and removed the ducts in the basement. Unfortunately our underpinners were very delayed (by more than 3 weeks at the time) so it got pretty dicey in the middle of November. We had a small heater which we snuggled up to every night and we took advantage of any heat source we had.

At its coldest, the house was 8 degrees (but I was too cold to take pictures at that point). It was really unpleasant.

We eventually moved out because we were having our floors done and didn’t have any floor space to sleep on.

It was also during a particularly cold week, so we were happy to get a break from being so cold. We eventually returned home when the floors were done, even thought we didn’t have heat. At this point we used the electric radiators (they were already there for our floors anyways), which took a small hit on our electricity bill. Although the extra $100 was well worth the comfort it brought us.

Building Permits

The building permit process was relatively painless, but not without its frustrations. We decided to submit the permits ourselves (to save $100) but the underpinner or engineer will often offer to submit these on the homeowner’s behalf. It wasn’t so bad, so the $100 savings was worth it. But I also had an insider in the building department to help me navigate through the system. It also wouldn’t have been so stressful if we had submitted the permit earlier.

The City of Toronto website says that the fast-track permit can be issued in 5 days. Now, I assumed that this meant 5 days from submission. It does not. A building permit will be issued within 5 days of when they start the review, and if all of the documentation is complete.

It took the City two days to begin my review and they required I submit a tree declaration form (which appeared optional but apparently was not). I also had to submit a permit for my neighbours (which was a surprise) because we’re technically underpinning one of their walls. So that was an extra $200 and a separate application form. Also, this technically made my application incomplete, so I was put to the bottom of the pile for review.

Luckily the rest of my application was very good. In particular, my drawings were good and this helped expedite things. Apparently the reviewers look for the quick wins.

I eventually got my permit 6 days after I submitted my application. In total, I got 4 permits: one for the underpinning at our house, one for the underpinning at our neighbour’s house, one for the plumbing work and one for the drains. In total, the permits cost us $585.54, which included an extra $33 because they didn’t calculate the amount properly the first time.

Then the City got really annoying. During the second visit by the building inspector, he told the underpinners that he required a signed letter from an engineer saying that the work was being done properly. Now, the thing that really gets me is that I’m not sure why I paid almost $600 for the inspector to basically not inspect anything. That signed letter, by the way, is $400. When I spoke to the inspector, he told me that everything was being done properly but that this was ‘standard practice’. If it’s so standard, the City should make it a requirement. My engineer was equally annoyed because it’s really the lack of accountability on the City’s behalf that caused this.

I can definitely say that based on my experience with the City, I will avoid future permits at all costs. The City is just difficult and completely unreasonable – and they have full authority to be. What’s frustrating is that the rules are unclear and favourable to the City so you don’t have any recourse when they come up with something that isn’t required or completely unnecessary. I mean, the $600 in permit fees were really just a cash grab.

The most permit drama we had was around our basement stairs. Because our underpinners cut our stairs off, we basically had to build completely new stairs. And building new stairs isn’t the same as extending existing stairs. And to add to the fun, the whole topic is pretty subjective and up to the individual inspector, which changed three times for us! So I had to fight pretty hard with the each inspector to not force us to build them to code. In the end, our final inspector was fine with the stairs and we were able to close off our permit with very not-to-code stairs.


When we started the underpinning work, the underpinners promised that hte work would be done in 4 to 6 weeks. Because Alex and I know a little bit about construction, we knew to count on at least 6 weeks, if not 8. 

Our underpinning job started on September 15 and the final concrete pour happened on November 19 – 10 weeks after they started. If they had finished everything by then, it wouldn’t have been so bad. But given that all of that time was without heat, it wasn’t the easiest 10 weeks of our lives.

They finally finished the job on March 4 – 24 weeks after they started. And most of that time involved us having to follow up and nag them to come and fix things.

“Surprises” and Scope Creep

I hate surprises. Especially surprises that cost money. 

Prior to starting the underpinning work, I talked to the contractor to understand exactly what “surprises” were typical in an underpinning job so that we could prepare for the worst. Alex calls me a pessimist. But I’m just a realist. Maybe that’s what all pessimists say.

One of the potential surprises was the height of the sewer drain pipe, which turned out to be too low. Luckily we had planned for the extra cost (around $3500) to dig down to the City’s property line. What we didn’t expect, however, was the cost to upgrade the water main. Since we were already digging, it made sense to do this work as well (an extra $1700). However, because our construction was so delayed and we had complained about a few things, we got a bit of a discount, so we only paid $1500 for all this work.

The other surprise we had was thanks to the City. We had to pay our engineer ($400) to complete a final report to confirm that the work was done properly and according to the drawings. Given that I paid for this inspection was part of my permit, I was pretty peeved. Luckily my engineer didn’t charge me as much as he should have, or else the cost would have been closer to $1,000.

The only added scope we had (besides our huge boiler and rad installation) was finishing the concrete floor. Luckily we had a bit of a window to do the work – between 4 weeks and 6 months – so it wasn’t an immediate cost. However, since we wanted to just finish everything so we could finally move things to the basement for good, we did it about 9 weeks after the final pour (mostly because we didn’t do anything at Christmas). Finding a (good) concrete polisher wasn’t easy, but we finally found one who quoted us $2800 for the work. Because of the crappy job our underpinners did, we ended up paying them $3500 (our choice). 

Because this isn’t Alex and my first rodeo with contractors, we were good at managing our budget and how we paid our contractors. Our stair guy, for example, only ended up getting half of his quote because he didn’t come back to finish the job. So the stairs cost us $500 instead of $1,000. This saved us $500!

We also kept a hold back with our underpinners. The hold back wasn’t part of the original contract, but as we progressed with the work and things weren’t going well, we kept a $3500 hold back until we were satisfied with the job. After a few blunders and the state of our concrete floors, we made it very clear that we would not pay a single cent of the hold back. I basically gave them two options: they could walk away from the job without getting the holdback, or they could replace the floor and do it properly (and pay for everything related to that fix). They wisely chose to walk away.

When you add everything up – extra costs and credits – the basement job cost us about $43,500. We were actually quite under budget (more on that in my cost post), but I would have been happier overall if I had paid full price and was happy with the end result.

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