Tag: slab

Basement Interior Wall Framing

Since we’re not framing the exterior walls of the basement yet, we went straight to the interior walls, specifically the permanent walls for the bathroom and mechanical room. After Mario put in the mesh for the concrete, I went around and carefully measured locations for the walls and placed J-bolts to secure the sill plates, so that once the slab was poured we wouldn’t have to drill into it. The main reason for this was the radiant tubing in the slab: if you drill into the concrete and hit a tube, that loop is basically useless, and our floor only has three loops. Unfortunately, Mario informed me the day of the pour that because of the way they were screeding and finishing the floor, the J-bolts sticking up all over would get knocked over and interfere, so he pulled almost all of them out.

First wall section

First wall section

I framed the wall in sections, pressure-treated sill plate and standard 2x4s, sill gasket under the pressure treated sill to prevent moisture wicking, coated screws for anything touching the pressure-treated lumber and regular screws and 8D nails for the rest. The uneven floor joists above required some shimming and I had to add blocking to a couple of sections where the wall was parallel to joists. I watched all my inside corners for drywall nailing edges and followed the tub instructions for framing around it. For the curb at the outside walls I built L-shaped pieces and attached them after the fact rather than try to build it with the section. I came back and installed an additional exterior half-wall for the utility sink and washing machine hookup, though in retrospect I might as well have just framed a full wall. I may reconfigure that, but I need to pick up some additional lumber since my original estimates proved low.

Bathroom framing

Bathroom framing

While the wall framing was pretty straightforward, we did run into some snags. For starters, the plumbers had put the toilet too close to the tub, something I could have had them fix if I’d noticed it before the floor was poured, say, back in October when they installed it. Because the toilet can’t move, I shifted the tub a few inches away, so the tub will have to use an offset drain and one of the few remaining J-bolts no longer aligned with the wall. They also managed to place a vent completely outside of the wall it was supposed to go through, but at least it’s inside the mechanical room where it won’t cause too much of an issue. I had to frame the wet wall of the bathroom with 2x6s because the plumbing alignment with the steel column wasn’t quite right, and I had to make some provisions for the steel beam that runs through the bathroom. In general, framing around all of the pipes sticking out of the floor was challenging.

Bathroom framing done

Bathroom framing done

With all the walls up and framed and a few J-bolts secured, I spent a lot of time poring over the photos I took of the floor after Lester installed the PEX tubing, determining where exactly I could drill the floor and secure the walls with Tapcon screws without hitting anything. After several nerve-wracking drills, including one gush of concrete dust that I was certain was air escaping from the pressurized tube, I had all the walls secure and the pressure gauge on the PEX lines holding near 70psi assured me I hadn’t hit any. Whew.

Now the plumbers and electrician are working on their respective pieces. Once they’re done and we’ve passed inspection we’ll get to insulation, drywall and putting up the temporary walls. I’ve got a list of smaller items as well, like hooking back up the water filter, moving the water heater, running venting for the bathroom exhaust fan, and ordering the other fixtures: vanity, toilet, faucets, and utility sink.

Basement Floor Acid Staining

Our basement floor is radiant heated and the ceiling isn’t all that high, which meant we wanted a flooring surface that didn’t interfere with the heat and didn’t consume any height. Staining and sealing the concrete slab was the perfect solution, and not terribly expensive to boot. There’s a number of tints, color seals, paints, and other options for finishing concrete, but we liked the texture and look of acid staining. After some browsing, research, and shopping, I ordered four gallons of acid stain and two gallons of lithium silicate densifier/hardener.

Washing the floor

Washing the floor

The first step was to wash the floor, and we made it a family affair with Sarah and I and the kids mopping and scrubbing. We’d been careful to keep the floor clean after the pour, and done things like painting before hand, but cleaning was still a necessary step. With that done we let it dry overnight, though the first step in staining was re-moistening the floor. I used a pump sprayer for most of the process, and the only issue we ran into was a couple of spots where water pooled and the stain didn’t take. I’d recommend mopping up any puddles first so you don’t have to reapply stain like we did. We let the stain set for about four hours; the longer you leave it the darker the color. Then we neutralized the acid by spraying an ammonia/water mixture and mopping and washing again. We weren’t quite satisfied with the color, so at that point we did another four hour stain on the lighter spots before neutralizing and washing again. One source said to wash until the water runs clear or the sealer wouldn’t take, but after several washes the water was still brown. Another site said we’d wind up taking the stain off if we over washed, so we finally called it “good enough”.

I came back the following day and applied the sealer. I was originally going to put down two coats of sealer, but it went on fairly thick, to the point that we’ll have to go back over it with a broom and then mop off the yellowed excess. As a result we still have a gallon of the sealer to use later, maybe when we finish the basement into an entertaining space in a couple years. When the other basement work is done I’ll come back and wax the floor to give it a bit of gloss, but we’re happy with the result.

Basement Floor Pour

We have a basement floor! Mario and his crew came out early yesterday morning and by 8:30 the concrete truck had arrived. In no time they’d poured the entire pad and screeded (leveled it out).At that point the rest of Mario’s crew left, but he stayed for the rest of the day carefully hand troweling the surface to a burnished finish. The pressure gauge on the radiant PEX tubing never wavered, so we’re confident that nothing was damaged during the pour.

Initial screed

Initial screed

There was one minor issue, in that Mario didn’t want to leave the J bolts I’d carefully positioned during the pour because he couldn’t smooth the finish with them in the way. I explained that I didn’t want to drill or nail into the finished concrete for fear of hitting the PEX tubing. Ultimately we left some of the J bolts in position and pulled some of the others. I took a bunch of measurements and photos to help me position new anchor bolts in the finished slab, but I’m not thrilled about the nerve-wracking possibility of hitting a tube and losing a whole loop of the radiant heat.

Finished floor

Finished floor

This weekend I plan to install the last of the basement windows and the back door. I’ve installed the window buck this past weekend to ensure I wasn’t going to be making any more dust. The next project is to stain and seal the concrete once it’s cured. I’ve been doing research on the specific products and techniques we’ll be using for that. I think with the finish that Mario put on the floor, it’s going to look really nice with the stain and seal.

Troweled finish

Troweled finish

This feels like a really important milestone. We started breaking up the concrete of the old floor over a year ago and never imagined it would take so long to get one back. We’ve gained close to a foot of headroom in the basement, a critical difference that makes it a much more usable space. In addition we’ve got the rough drainage in place for our basement bathroom and utility sink, our new water main and sewer, and an interior weeping system that at this point really needs to be hooked up, since the sump basin has almost completely filled with water! With the new windows, the new back steps, the painted ceiling and beam, the tuckpointed brick walls and the all new electrical outlets and lights, it’s a night and day difference from where it was. While I really expected to be at this point in October, I’m happy that we’re finally here now and looking forward to the steps ahead.

Basement Floor Prep – Plastic, Mesh, and PEX

As planned, Mario (our concrete mason) came out on Monday of last week and put in the plastic vapor barrier and the wire mesh on top of the foam insulation. Over the weekend I installed “J” bolts (they’re shaped like J’s) where our interior walls will go, so we don’t have to drill or nail the new concrete slab. I cut short pieces of steel rod and stuck them into the foam and then wire-tied the J bolts to them to keep them positioned and upright.

Basement PEX tubing

Basement PEX tubing

Today Lester, our radiant heating contractor, came out and installed the PEX tubing that will eventually allow hot water from the boiler to keep our concrete slab nice and warm and heat the whole basement. Once the tubing loops were run and zip tied to the mesh, he pumped compressed air in to 70 psi as a pressure test to ensure the loops are air (and water) tight. They’ll stay pressurized during the concrete pour and cure to make sure they don’t get squeezed anywhere. He gave me a list of warnings to pass on to Mario and his guys when they’re pouring the concrete: when they’re using a concrete spreader, don’t hit the tubing! When they tip up a wheel barrow, don’t hit the tubing! When they’re running wheel barrows back and forth, lay down some half-inch plywood so they don’t hit the tubing! I sensed a trend.

Also basement PEX tubing

Also basement PEX tubing

Mario is planning to pour the floor on Thursday, and I’ll be there making sure that Lester’s instructions are followed. If anything happens to the tubing during the pour and it leaks, our whole radiant-heating plans will crumble. The only choice would be to tear up the whole brand new concrete slab and start over, or switch to hot water forced air in the basement, and with the lack of head room I don’t want to run ducting!

Basement Floor Prep – Stone and Insulation

Mario, our concrete mason, came out on Saturday and put down the stone that makes up the bottom layer of our new basement floor. I had hoped that he would also install the layer of rigid foam insulation that makes up the next layer, but apparently that’s not in his menu of services, so I was on the hook to do it myself. More than that, he wanted to come back on Monday to put down the plastic and the mesh, so I needed to get it all installed on Sunday. My friend Dean and his dad, Hector, once again offered to help.

Insulation delivery

Insulation delivery

The first challenge was getting the insulation. We’re using 4′ x 8′ panels of 2″ thick XPS (extruded polystyrene) foam, which are commonly sold in different densities. The higher density foam is better for under concrete because it doesn’t compress as much. Unfortunately it’s not stocked in as many places and I was buying 30 panels. I placed an order Saturday morning at a Home Depot that had “99+” in stock. By late Saturday afternoon the order still wasn’t ready, so I called them. After being on hold for 15 minutes I was told they “couldn’t find it” and apparently had zero in stock. There was only one other Home Depot near me that had enough in stock, so I switched the order to them. They had it ready by 6:30. Unfortunately they didn’t have a truck available, so I wound up renting a truck from a Menards that was nearby (they didn’t carry the foam). I went to Menards and got the truck, drove to Home Depot, manhandled the five-foot-tall stack of foam onto the truck, drove the truck home and dropped off the foam in the back yard, drove back to Menards to return the truck, and finally drove back home.

Sunday morning came earlier than expected (due to the Daylight Savings time change) and Dean and Hector showed up. We started at the front of the basement and worked toward the back, using the hand tamper and a rake to even out the stone base in places. The concrete curb around the footing and the column footings have rough edges that we couldn’t get the foam completely flush with, but we worked around them as well as we could. The bigger challenge was the plumbing. Because the plumbing in the basement drains to an ejector pit, the pipes aren’t particularly deep. That meant in addition to cutting holes for the pipes themselves, we had to allow for horizontal pipes and fittings as well, not to mention the sump basin and ejector pit. Overall the process went smoothly and after several hours we had everything installed. I did some foam sculpting to cover up the bathroom plumbing group and I’m pretty pleased with the end result. We were frugal enough with the foam panels that I have seven left over to return. Since they cost me $32.50 each, I’m happy about that.

Insulation installed

Insulation installed

Mario is back today to put down the plastic and mesh, and then Lester (our radiant contractor) will be out next week to attach the PEX tubing. Mario should be able to pour shortly thereafter. We’re still working on the painting and prep for the front window and back door. I hope to have posts about those projects shortly. A big thanks go out to Dean and Hector for all their help!