Well after a couple fits and starts we're officially back to work. If you recall, we were still fighting the weather on Monday but yesterday we were able to build this.
The enclosure is more to protect the concrete then the crew but the guys appreciate it as well. It was pretty nice out today but that's not likely to last. We built the enclosure with pipe staging and reinforced poly stretched over lumber frames, which will facilitate moving it to the next location. We'll heat it with a couple 200,000 btu propane kettle heaters.
Today we got started on some formwork. You've seen this formwork system before on the mock up we did back at the shop. Here it is in place.
The formwork consists of 4x8 panels with an 18" extension on the top to get us enough form to place the 9'1" walls. I took great pains to design the formwork so that the panels' seams and tie pattern are uniform and symmetrical. Kind of like tiling a floor.
After caulking the plywood edges, we used pipe clamps to pull the panels together as tightly as possible before installing angle irons across the seams to hold the panels as flush as possible. The caulk will make the formwork waterproof to prevent sand streaking and provide a uniform surface.
Once the panels were aligned, we added a double 2x6 horizontal waler to hold the top of the wall straight. We used
Tapcon screws to affix the bottom of the form to chalk lines we laid out the concrete slab.
This wall is over the
LiteDeck that covers the basement where the radiant tubing is only an inch or so down. All those photos I took sure came in handy.
Here's a shot of the final surface with the coil ties installed.
This is a portion of the concrete that is an exterior wall of the home where the
Thermomass will go (if you refer to the plan in post 1018, you can see it towards the top of the walls to the left of the drawing).
The
Thermomass follows the rigid insulation that separates the slab from the foundation wall. We'll drill & epoxy some bars into the foundation to anchor it down and resist overturning.
By the way, if anyone is curious about the two opposing U shaped walls. The wall to the left creates a duct/pipe chase that runs from the basement to the roof. The one on the right encloses a 70" linear gas fireplace
One final detail to share. Remember the threaded rods we welded to the tops of the beams before we placed the
LiteDeck slab over the basement? This is why we did that. These concrete wall sit on steel beams, not footings so we need something to keep them from falling over. The threaded rods, nuts and washers will keep the walls securely attached to the structure.
You can also see the foam tape we stuck down to the concrete to seal the plywood form to the slab - watertight right?
Pretty good progress for a couple cold February days. Still hoping to get these first two walls placed this week to take advantage of the weekend for curing time so I can pull the panels Monday and do it all over again.
The next sequence should go a little quicker because we'll use a crane of some sort to move an entire form side as a unit.
It's fantastic to be back at it!
