As anyone who owns a home knows, it's not always rainbows and sunshine. There's always something that needs to be fixed or replaced. Most recently, the sewer line under the concrete slab in our family room needed to be replaced. Cha-ching!
We noticed some significant settling going on in our family room last spring. We thought it was just some random settlement and decided to try to mudjack the floor. While the mudjacking appeared to have fixed the problem in our family room at first, over time it started to settle again. We really noticed this when Adam brought in the new aquarium stand he is building into the family room. He realized the floor was incredibly unlevel and had settled since we had the slab mudjacked back in April. (You can see in the photo below how much the aquarium stand would have needed to be brought up in order to be level on the floor). Adam, being an engineer, used all his knowledge and figured out there had to be some sort of water or leaking causing the settlement. It turns out his guess was correct. After having a sewer line inspection, we found out the sewer line below the concrete slab in our family room was broken. It was completely disconnected. And all the water we were using in the showers, toilets and washing machine was just pouring out of the disconnected pipe. There was also a section of the pipe that had a belly to it, so instead of water flushing through the pipe, it was just hanging out in the low spot. To say we were shocked was an understatement.
While Adam is an engineer, he wanted to get some other perspectives from engineers who specialize in residential engineering to help us figure out what to do. So he consulted with two different residential engineers to help us figure out the best course of action. Adam's uncle who has significant knowledge in construction was also able to give us some insight. After taking everything into consideration, there were two options for fixing the broken pipe.
One option was to trench around the pipe in the concrete slab, replace the broken section and low bellies of the pipe, then pour back concrete where the trench was. This was the least invasive and easiest fix. However, we weren't sure what all that water had done underneath the slab. The fact that the slab was settling in multiple areas led us to believe it had washed away a lot of the gravel underneath the slab. So even if we fixed the pipe, there could still be continued settling since we wouldn't be able to backfill all the areas that would need more gravel.
The other option was to completely demolish the existing concrete slab. That way we could replace the entire length of the pipe and replenish all the necessary gravel to prevent settling from happening in the future. It would also give us the opportunity to tie the floor slab into the stem wall foundation, which it was not previously tied into.
Ultimately, we decided to completely demolish the existing concrete slab. This, of course, was the most expensive and challenging option. Luckily, Adam had a solid understanding of everything this project would entail and took on the role of general contractor. He arranged for three separate crews to tackle three separate jobs. But before any of the crews could start their work, we had a lot of prep work to do.
Adam did most of this work, though I tried to help out when I wasn't doing all the everyday kid and house stuff. My dad also was kind enough to help out. All the furniture had to be stuck somewhere else. The carpet (that we just had installed in April) had to be removed, along with the carpet pad and carpet tack. Part of the flooring by the entrance from the garage had to be taken out and the steps that lead up to our kitchen. The toilet and vanity in the half bathroom had to be taken out, too. And the vents needed to be sealed off to prevent a bunch of dust from getting into our HVAC system. Since the concrete slab was going to be removed and a new concrete floor was going to be poured inside our house, we wanted to contain the construction zone as much as possible. Adam made a temporary wall to block off the family room from the rest of our house. This definitely helped keep the project zone contained, which was super nice. Though it meant we could no longer access the garage or basement.
Once everything that needed to be removed was out, Adam moved onto protecting what was left in the room. He put up plastic sheeting, polystyrene and pipe insulation around the door frames. (I'm not gonna lie, using all this plastic and Styrofoam in our home made my sustainability-seeking heart hurt. But we figured protecting the woodwork and drywall we had would prevent us from having to replace it after the concrete was poured would ultimately be the better option. Adam was also able to pass along the polystyrene to someone else to use for another project). Getting everything prepped for the first crew to come in was a job in itself!
At this point, we were ready for the first crew to come demolish the existing concrete slab. Adam decided having the concrete cut into sections using a wet saw, as opposed to having it jack hammered out, would be far less dusty and result in far less damage. We went with a local company that specializes in this sort of work and were very happy with the results. The kids and I stayed out of the house while this was going on to avoid the noise, while Adam stuck around to manage everything. As you can see from the photo below, once the floor was cut, it sunk quite a bit in many areas. This told us there were voids underneath the slab and made us realize we had made the right choice by taking out the whole slab. Once the sections were cut, the crew removed all the sections.
We were left with a giant gravel pit. We weren't sure exactly what to expect once the concrete slab was removed. There was a chance we would need some sort of remediation since sewage was essentially pouring out of the broken pipe. But we got lucky in that regard. We didn't need remediation and there was no smelliness to deal with either. The second crew stepped in at this point. They worked on filling in the voids, digging to the broken pipe and putting in some piers to help further stabilize the new concrete slab that would be poured. Here's the broken pipe. It's a little tricky to tell from the photo, but there's a giant gap!
Now that the pipe was unearthed, it was time for the third crew (the plumbers) to step in. They took out the old sewer line and replaced it with a new PVC one. This took care of the broken segment and also the belly in the pipe. They did have to drill a new hole in our basement wall to make the slope of the pipe work correctly. Obviously the water had to be turned off while this work took place. The kids had preschool in the morning and then I kept them out and about for the rest of the afternoon, while Adam kept an eye on the progress.
Once the plumbing was wrapped up, the second crew could come back to get things prepped for the new concrete slab. They worked on putting in the piers and leveling the grade.
Next came putting down a vapor barrier to help with moisture and to help keep the family room floor a bit warmer. Laying the rebar happened after that. Once the rebar was in place, it was time for the concrete!
Here's where things got a bit tricky. Things had been going pretty smoothly and on schedule up until this point. But the morning the concrete truck was supposed to arrive, things went awry. The pumper truck arrived and got their hoses hooked up. Then everyone waited and waited for the concrete truck to get here. When it finally arrived, it was well beyond when it was expected. I don't know much about concrete, but apparently you have a time limit from the time it gets mixed in the truck to the time it is poured. Our time limit had expired and the pumper truck guy didn't want to risk the chance of the concrete drying up in his hoses. The mix also wasn't the exact mix that Adam had specified. So we sent the concrete truck back. This was a real bummer, but we also wanted to make sure everything was done correctly. With the amount of money we were spending and the time we had invested, we weren't going to take any chances. So we had to reschedule the pumper truck and the concrete truck for later in the week. Luckily, things panned out the second time around. And one silver lining was that Archer and Lyla got to be around to see it all happen since they were at preschool during the first go around.
The concrete got poured without a hitch. The crew got it all smoothed out. And now our floor is pretty darn level! It's not one hundred percent perfect, but it's close enough. The fact that we kept the walls by the half bathroom in made it tricky to get the floor completely level. But taking those walls out would have resulted in even more work and money and time, so we are pleased with how everything panned out given the constraints.
