Day 293

When I last mentioned the status of our house remodel, I told you that I had a foundation repair expert out to look at some weird movement in one of the cement slabs in the living room of our house. He suggested that we install two slab piers to stabilize the cracked portion of the slabs and prevent further movement. He also told me it would be 4-6 weeks.

But then they called me last week and said they could fit me into their schedule early, and they came out last Thursday.

Here's how it looked in the morning before they arrived. The problem was along the vertical crack, near the top of the photo. The left side of the crack had fallen down below the level of the slabs above and to the right of it.



First up was the guy with the concrete saw to drill two holes in the floor. IT. WAS. LOUD. Good thing we only had two holes to drill.



It left such perfectly pretty little holes in my floor.



Then they placed some little gizmos in the holes with brackets that fit up under the slab on two sides.



Yes, it was slightly unsettling to stand in my living room and see the dirt that has been living under my house for about 40 years or so. Even weirder was their observation "You've got good dirt!" (We do live in an area famous for its peach orchards and vineyards...)

Then they set up the hydraulic gizmo that pushes sections of galvanized steel tubing through the first gizmo in the floor.



They turned the machine on and sloooowly inserted one section of tubing at a time until they reached something really solid underground. All the while, they were watching for movement in the slabs on either side of the crack.



They pushed 16 feet of tubing into the floor and had it at 1,000 psi. That's 1,000 pounds per square inch, folks. That's a lot of pressure pushing up on the floor! Unfortunately, although the sunken part of the slab was lifting, so was the other side that needed to stay put! I think the way the crack developed in the slab, the part on the right was hung up on the part on the left of the crack and had no choice but to move up, too. They assured me that the two piers they were installing would prevent further movement, so I told them to proceed as planned and I'd just grind down the higher part before finishing the tile.  

I went back to work in my office at the back of the house while they went to work pushing the tubes into the second hole. As they worked on it, I thought it sounded very different from the first hole. My fingers paused over the keyboard as I heard creaking and moaning in the walls and ceiling. I held my breath.

Then I heard a loud pop and a quiet voice come from the living room saying, "Well, that's wasn't good."

I held my breath a bit longer. My fingers hovered over the keyboard. I decided I didn't want to know, so I went back to work.

After several minutes of discussion, they relieved the pressure on the hydraulic gizmo and I heard the creaking and moaning as the walls and ceiling relaxed again. I held my breath. I decided I still didn't want to know. So I went back to work.

After a few minutes the foreman came back to get me. It turns out that at 17.5 feet and with just 400 pounds of pressure, a rather large piece of the slab over the bracket broke. ACK!



Fortunately, they were able to rotate the brackets to get them under a solid piece of the slab and proceed as usual. They equalized the pressure between the two piers, sawed off the bolts below the surface of the slab, and filled in the holes with new concrete.



Unfortunately, the installation of the second pier lifted the whole slab even more, so that the slab on the right side of the crack (on the left side in this photo) was lifted higher than the slab next to it (they used to be perfectly even).



And because this is the joint where I already had some cracks in my tile... Well, you guessed it.



I'll have to tear that tile out and probably at least the one to the left of it, maybe even a few more of that row. That's not exactly an easy thing to do with this kind of tile and the mortar we used. But hopefully this at least means that the new tiles I install won't crack again due to a moving floor. We shall but hope, right?