04/24/2017
Part 4: The Foundation (chapter two)
To recap, our cabin was going to be 12x16’, and the foundation would be concrete piers (basically, columns of concrete that stick out of the earth, and the house sits on them). We were going to set it on 14 of these concrete piers, all of which needed to go down at least 4 feet below the ground. Let me repeat that in case you missed it: WE WERE GOING TO HAVE TO DIG 14 HOLES, EACH 4 FEET DEEP, IN SUPER ROCKY GROUND. The reason is that, in the cold climate of Vermont, the frost line is 4’ deep. If you are above the frost line, the frozen ground can literally lift the whole pier upwards, doing god-knows-what to the house above it.
I’m getting ahead of myself. In order to mix concrete, I figured we would bring buckets of water up from the brook and pour it into the wheelbarrow. Our friend Dale, who is an experienced builder, assured us that we would be doing no such thing. To mix the quantity of concrete that we needed, we were going to want a continuous supply of water. For that, we’d need a water box.
Now I mentioned that there is a cliff behind our land. It turns out that a brook trickles down a gulley next to the cliff, and that this brook may very well originate from a spring on the mountain above. To test this, our man Dale drank straight from it, and when he didn’t die within 24 hours, we considered our brook potable.
In order to get running water, we constructed a 2x2x2’ box out of pressure-treated lumber, which had no bottom and no top. To let water into it, we bored a 1” hole in the backside of it. We dug out part of the brook and buried this box in it, lining the bottom with stones, so that it filled with water—then we took a 300-foot black hose and siphoned water through it, so that it gravity-fed water down to the homesite. Success! (see the pictures)
Now it was time to start digging our holes. We needed 14 of them, so we spaced them out using our carefully placed strings and began digging. Dale had warned us that the property looked “ledgy”—that is, it looked like it had a lot of rock running under it—but we were hoping that we’d luck out and no hit rock on our 56 cumulative feet of vertical digging. And guess what?
We hit rock. We hit rock 14 times.
What ensued were 2 torturous days of digging, crowbar-ing, pickaxing and playing the role of the Miner Forty-Niner right down to the drooping hats we wore to protect our heads from mosquitos. We’d sometimes get down 2 feet and hope that there would be no problem, and then we’d hit rock. Other times we would get down 2 inches and hit rock. Either way, we hit a lot of rock.
Architects told us to do something elaborate involving a hammer drill, a large bolt sticking out of the rock, and other things. That sounded too hard to me, especially given that we didn’t have a hammer drill, the air compressor necessary to run it, or the willingness to spend any more time underground. The solution we came up with:
1) blast through the soft rock until we hit hard granite
2) clean the granite
3) pour the concrete directly on it
To be continued.