On Thursday we started a new project in North Asheville, creating a formal entrance as part of an extensive house renovation. The entranceway was designed in collaboration with Tony Hauser and Beth Gillespie of Ambient Design Group. This project has been in development for over a year and so it’s very exciting to actually be on site and working.
The house site is situated down a steep slope and the house entrance is a few feet below the driveway grade. A block wall retaining system holds up the driveway. It was suggested that we apply a stone veneer to the block wall. I have never seen this done and perhaps it is a standard practice somewhere, but it seemed like a very poor choice. The block wall is dry laid. Though it’s unlikely to move, it still has that ability. Building a rigid structure on the face of a flexible one seems to be inviting disaster. Leaning a dry stacked stone wall against the block wall was also suggested, but our stone wall would have only been a foot thick and not at all integrated with the wall behind it. I decided that the best solution would be to have a distinct footer for our work. The walls we’ll build will be structural, free-standing, sitting squarely on their own deep footing. This will be a little bit of stone veneer applied to the house foundation to blend the work together.
The first order of business was to install several granite monoliths, standing upright on a concrete footer. We used nylon straps, chains and Lewis pins to rig the stones so they could be lowered into the hole with the excavator. Danny Joe Brown, the excavator operator, removed the bucket to reduce the boom weight and to fit the arm into smaller spaces.
The machine, a 12,000 pound Bobcat, handled the work perfectly, even when craning 3,000 pounds rocks into a six foot hole. Danny Joe has 25 years experience and it showed. We all felt completely safe and never once had a worry that we or the property were in any danger.
We used Lewis pins drilled into the top of the stones to set the smaller rocks. These pins are rated for 3,000 pounds and are placed into drill holes without epoxy; the angle of the lift pulls the pins tight and prevents them from slipping out. The rigging is cinched so tightly to the excavator thumb so that we could slide the stone underneath the eaves of the house. The gutter and fascia boards were only about three feet above the top of the stone. Tight rigging and deft excavator work made all the difference.
The first monolith in place. The random board on the house is a bumper that will be removed later. Wood siding will disappear into that space with enough room for air circulation to ensure the boards don’t retain moisture.
The view from the driveway at the end of the day. We didn’t use the Lewis pins to set the two monsters that frame the top of the steps, each weighing over 3,000 pounds. We lowered the giants down into the hole flat using chains wrapped around their middles. We then stood them up by wrapping them with nylon straps that cinched the tops snugly. We could do this because the stones were tall enough so that, once placed, the straps weren’t pinned against the block wall.