Floors Cast in Stone

SUMMER of 2021 —It was a magical feeling when we lifted our first wall—turning what’s in 2D into a 3D construction. The first corner and our very first window appeared just in few hours. But then we got stopped once again when we realized that we forgot to update the structural plans when we made cHaNges to the window sizes.

Our engineer has been great in many ways; BUT he has been a pain to get a hold of. So we had to pivot not to loose time. Next on the list was concrete floors and the radiant floor heating. This was something we’ve never done before like many other things on this project. But we worked on the plans when we prepared our paperwork for the permit. There are few details to know when it comes to installing the pex-pipes and as good students we did our research well ahead of time. So we only had to recall what we had forgotten. :) Fun fact: the uncoiling the pex-pipes for the loops was “fun” and only took us two days to finish.

Casting the floors with concrete required a bit more guts and courage… We were nervous and wanted to do a good job on this. We watched countless videos on how to pour concrete floors by professionals. Got all our tools and emotionally prepared ourselves for the challenge. Or at least we thought we did….

The process goes like this: pour, rake, screed, float, edge, trowel and water until it sets. This is one of those trades that is highly specialized for a reason. It requires proper timing, teamwork and good technique. So Ece suggested May be we should bring someone in to do this? But Ivan was Nope! With that, started our journey with concrete.

If everything prior to this part of the house had generally one right way of doing it, with minor nuances on the approach, the opinions on how to do the proper concrete floor varies a lot. There is plenty of information online; but when you are trying to figure something out, it all contradicts each other. Some people say you must put a rebar or a metal mesh or it would crack and lift, others say it must be at least 3” thick. And then it doesn’t apply to concrete covering over the plywood. Then you find a solution of putting the microfibers into the concrete for strength, but forget it if you’re planning to polish it because they would be sticking out of the surface. Architects clearly allowed for only 1.5” of concrete on top of plywood, so that was that, and they even recommended a specific self-leveling product to use, and we wouldn’t have to worry about raking and screeding it. Which sounded great, but would’ve cost us around, give or take, $70000, and I didn’t put an extra zero in there, that is literally 23% of our original budget. Than there is gypcrete which is apparently is a bastard child of gypsum and concrete. It has a thermal capacity of concrete and lighter than concrete but you can’t have it as final surface.

So for many reasons, some are more obvious than the others, we had to plunge into this part of the project half blindly. After visiting a local concrete plant, they just told me to use the sand mix because, even if the smallest stones would be used, it would be impossible to trowel without those stones sticking out. There was never a point of finishing the research rather coming to terms with the things we found out and leaving the rest to the future us to deal with. The final decision was to pour the sand mix, simple and cheap and in worse case scenario if we really don’t like the results, cover the whole floor with something, like thin layer of epoxy or self levelling.

A major considerations we went through in our heads was; if we should order a concrete truck or do it ourselves. Pros of bringing a truck was that the concrete would’ve been already mixed and ready to pour in few hours. We didn’t have to worry about mixing it or pouring it; however, we had to worry about working the concrete before it sets. Normally, it takes a team of 4 to 5 people on the ground working like a beat, spreading and screeding the concrete as it’s being poured; so that, it’s even without any air bubbles. Then someone floats to get a smooth surface. After waiting for the right moment, next person does the edges and then, the final process of troweling starts. This is like polishing the surface of the entire floor using a machine or hand to make it really smooth. As you know we’re only 2 people, with no experience working the concrete; so we had to get some. So first thing first before experimenting on the house experiment elsewhere! We decided to pour a “little practice slab” at the entrance of the property to gauge the speed we can work with and get used to all new toys we got like floats and trowels. The size of the slab was dictated by the usability and our undying maximalism, and the thickness of 3-4” is by general good practice. Since it was middle of the summer we decided to pour after the noon heat and definitely regretted it. The thing about concrete is when you start it there is no going back or even slowing down. We were absolutely exhausted by the end of pouring it yet we still had to float and trowel. Troweling went all the way into the dark. That was unintentionally one of the toughest and memorable days of the construction, that really helped as gauge our absolute physical limit.

Day 1: For good or for bad the concrete pump was not available for two weeks, so that gave us an excuse to separate a small part of the house and pour the floors there for the sake of the experiment. Based on our finding we needed at least one more person for this job. Ivan would be mixing the concrete, the other person would wheelbarrow it to the place and Ece would spreads and screed. Screeding is done with a large peace of wood, so it really requires 2 people to hold on both sides. Our neighbour Jeremy helped us with this process. It took approximately 2 hours to pour a section and then we waited for 2 to 4 hours before troweling. We hand troweled the surface ourselves. Honestly the troweling turned out to be the most stressful of all because it required a certain state of dryness / wetness which was affected by the outside circumstances. The first day wasn’t perfect but we were on a really steep part of the learning curve and area being a couple washrooms and a mudroom didn’t really bother us.

Day 2: It was time to raise the stakes. The area had been 2-3 times larger than the first day, and also being the living room/kitchen of the separate unit , we had more pressure on us to finish it nicely. And we botched it mercilessly. It all began fairly well with Jeremy helping us for the most part and it seemed like we had plenty of time to finish before the concrete sets due to cloudy weather. But that was our undoing. By the time we were finishing the kitchen we were absolutely exhausted, it started raining. The concrete was setting we were a bit behind on troweling and the rain added even more texture to it resulting in the most uneven finish in the entire house. It wasn’t finished but we were done with it. I can’t say I’ve ever regretted leaving that floor as is, rather it was an admittance of us reaching our absolute limit and being fine with the result no matter what it was.

Day 3: The thing about concrete finishing, you don’t want a very sunny weather because it will set before you finish pouring it. On the other hand, sure as hell you don’t want it be raining either because it will ruin the surface all together. Preparing to do the rest of the west side we knew it might rain so we decided to pull a tarp over the whole area we were working on. Luckily we had bunch of tarps from the previous year covering up all of the sonotubes and later material throughout the winter. And I have to say, it almost worked.

The whole thing would’ve been fine if not for a literal rainstorm and a couple of tiny wholes in the old tarps. The deafening sound of the rain and the water flowing off the tarp in a waterfall are solidly imprinted in my memory, but actually didn’t affect our work that much. On the other hand a couple holes in the tarp that allowed some water to seep through and drip on to the finished surface very much did.

Because of a much smaller space, we managed it much better than the living area. Though, every place that had some dripping have left a little puddle of flacking concrete on our finish.

Day 4: This was a beautiful sunny day. Partially to take a brake and partially because of the scorching sun, we decided to pour a rather small area at the entrance of the house.

The weather was perfect and we didn’t have to strain ourselves. We really seemed to get a hang of this whole thing. It was one perfect concrete flooring day. On the flip side we had to water the entire house regularly so the concrete wouldn’t crack too much from drying to quickly in the sun.

Day 5: We were pouring the main house kitchen, and it rained… We didn’t know it when we started but it was another rainstorm going through. We knew what to do this time and readied the tarps. This time we didn’t have the walls to stretch our tarps from so we had to construct the entire structure with scaffolding and quickly made masts, to form a yurt over a patch of floor we were working on. It was a continuous struggle of covering everything from being damaged while at the same time leaving access to float and trowel.

Luckily it was middle of the summer, so getting wet wasn’t really a concern. It was another controlled disaster day. We finished just fine, like any other day, but concrete was left with some scars to show for it. Because of the time it took to run around and cover things some concrete actually managed to set under the water before we could trowel it, missing that perfect finishing surface.

Day 6: We were exhausted physically and emotionally so we took a day off before getting back to it. We poured the mechanical room, small and relatively inconsequential part of the flooring. That worked quite well without any accidents.

Now we were preparing for the gruesome task of pouring the living area of the main house, the biggest and the most visible part of the whole house.

Day 7: To be clear roughly ten days passed between day 6 and day 7. We were lucky to have some other commitments at that time, so we had time to rest and choose perfect day for the job. We had more experience of finishing concrete than ever before and were going to take it head on.

That was the most satisfying controlled pour that we had, but not without its flaws. Even though there was no rain, the water still pooled in the centre making some concrete flake. Looking back after making a couple more pads over the years (5 more and counting) The reason was probably mistake at the ‘screeding’ stage. We didn’t spread concrete evenly enough so it lacked a bit of substance in the places it pooled.

After our seven days, we finished the job, but all of the experience we accumulated along the way showed on the floors. In places absolutely perfect but in places really lacking. Like with many other parts of this project the job was done but not quite finished, leaving some consequences to the future us to deal with. In the meantime, we received the word from the engineers and were ready to move on with our carpentry.

Fast forwarding two years to 2023 to the future us that were finally forced to deal with it. We have spent a good week filling some cracks, grinding some unevenness, wet polish and dry polish, and finally sealing it. We could keep fixing it indefinitely but eventually we had to come to turns with how much is enough, and with a bit more time actually learned to love the unique and authentic texture of the floors it took us so much effort to create. It’s the Wabi-Sabi of our house.

Here are some other things happening in our lives in the mean-time: