As we arrived Thursday, Terry informed us we’d receive a concrete delivery from Harrison around noon that day to place the footers. No slacking that morning – lots of work to finish our forms and reinforcing in time. The work included inserting PVC pipes for utilities and cutting 2-foot rebar dowels that will join the footers to the ICFs.
Harrison arrived right on schedule with one mixer (9 cubic yards) and their pump truck, a massive vehicle-mounted crane whose sole purpose is to deliver concrete through tubes to a point far from the mixer. Terry held one end of the tube and walked it around the basement perimeter as it steadily puked wet concrete. Meanwhile, he told Colin and me to grab shovels, rakes, and implements of destruction. We followed the pour around the perimeter, troweled the concrete surface flush with the top of our form, and carried shovelfuls from the high spots to the low spots, trying not to spill any over the sides.
Once the concrete was reasonably smooth, we skimmed off the excess with 2×4 screeding bars. A light rain helped to level the surface and highlighted the low spots for us. We allowed the concrete an hour to set up a little, then we clipped our horizontal rebar zip-ties and stuck in the dowels at 4-foot intervals.
Colin was concerned the footers wouldn’t set fast enough in the rain, but by Friday the concrete felt solid and we had no trouble removing the inner formwork. Actually, the biggest problem with the weather was drainage. Pillsbury left their excavator on site, and Carson, celebrating his first day of summer, climbed aboard to dig a temporary trench into which our deep puddles could flow. Not many high-school juniors can operate heavy equipment like Carson can; I’m excited to work with him all summer.
With formwork removed and drainage taken care of, we were ready to build the basement walls! We ferried ICFs down into the hole and began laying them out one layer at a time with the outer edge 3½ inches inside of the footer. They really do stack together just like Lego bricks. The interlocking protrusions on an ICF repeat every 2 inches and the pattern needs to line up exactly; fortunately, the foam is very easy to cut with a hand saw. As we built up the wall we staggered the joints and alternated the corner piece orientation for each course. We snapped horizontal rebar into the webs, hand-bending the bars around corners, and we zip-tied each module to the course below.
By Friday’s end we had five courses stacked 80 inches above top of footer, enough to reach the mudroom floor height. The raised first floor will be two courses higher. Shooting for our next concrete delivery Tuesday to fill the ICFs.