Spiral Stone Staircases

by Aaron Wilson


Text by Joanne M. Anderson  |  Photos by Kristie Lea Photography

Some 20 years ago, David Conroy built a fireplace for Jimmy Tannahill’s parents, Jim and Lori Tannahill. About 10 years ago, Jimmy, owner of Tannahill Truck and Bus Repair at exit 109 off I-81, purchased a 102-acre parcel with a mountaintop site and 100-mile views one ridge over from his folks in rural Montgomery County. He moved up a single wide trailer. “You hauled that trailer up the narrow, winding, dirt driveway?” someone asked incredulously. “Oh, no, there was no driveway back then. We pushed it up the side of the mountain with a front end loader,” Jimmy says with a grin. Like many homeowners with a vision, Jimmy sketched the house on a piece of scrap paper, first the prow front all glass west and south facing structure, then the fireplace and spiral stone staircases behind it.
Conroy, 53, is a brilliant, creative, stone mason, so Tannahill asked him to build two very unusual staircases. “He wanted an all natural, locally-sourced, stone chimney three floors high with curving stone staircases behind two fireplaces, one from the open lower level to the first floor and the other to the second story master suite,” Conroy explains. “Plus a stone section behind the lower level fireplace for a woodstove and another one on the second story. Plus lighting. And three electrical outlets. And cantilevered stone seats. It was a once-in-a-lifetime kind of project.”
David Conroy was destined for a career as a stone mason since childhood. His parents, John and Loretta Conroy of Floyd County, had to make a rule when they went camping that David could not bring home a rock bigger than his fist because of his penchant for collecting rocks. Later, when he no longer accompanied the family on camping trips, Loretta would find a rock to bring back for him. No bigger than her fist, of course. He was enamored at a young age with stone castles in a children’s book. He does not recall the title, but when Jimmy asked him about constructing a 3-story, native stone fireplace with two spiral stone staircases behind it, Conroy remembered seeing such a thing in his castle book. He had the vision before they began the plan.
Jimmy sketched out his ideas, and Conroy knew they’d need some approvals. He took it to Z. Van Coble, licensed architect and assistant provost for academic space at Virginia Tech in Blacksburg. “The great challenge was being code compliant in terms of height and width,” Coble recalls. “You need 6 feet 8 inches of clear height and clear width of 36 inches. This was tight, and the stones would take up some of that vertical space.” Reluctant to be the only one sealing the document, Conroy brought in Mike Fitzgerald, a structural engineer with Balzer and Associates. “He had some great input,” Coble continues, “including how to support the stone arch overhead which was shallow.” To Fitzgerald, it was the most unique stone and concrete structure he’d worked on. In fact, he still has the drawing on the wall in his office.
The chimney and fireplaces were constructed first from the bottom up. “The whole thing rests on bedrock, and we estimate it weighs around 150 tons,” says Michael Bailey, Conroy’s lead mason and right-hand man. The entire project consumed 120 tons of stone, which was hand-picked, loaded, transported and unloaded by Conroy and his crew of three. They hauled all the rock in Stone Age Masonry’s 1979 Ford F-450, 4WD, red truck which Conroy bought new off the showroom floor. It was dumped outside the still open framed house, then loads were driven into the basement in a Bobcat T190. Bailey has been working with Conroy for 17 years, and he recalls: “The whole room was a big rock pile. We set up two stone tables, two by three feet each to work on; there’s no way any of us wanted to break our backs splitting and facing rocks on the floor for six months.”
“Before starting the stairs, I had to figure out where every stair tread would be. We’re only permitted a 3/8″ variance on the stair riser, and we needed to plan the lighting.” Conroy drew the details on a wall in the lower level where the staircase construction commenced. They built a wood arch out of 3/4-inch plywood with radius cut at the top and a wood 2 x 4-inch wall on each side, then laid everything in sand first. “Once you have the forms in, you can’t get back in there, so everything has to be planned precisely,” Conroy states. “The lights needed to be equally spaced at the right heights in the staircase wall.” All the electric wires are encased in 1/2″ PVC pipe for conduit, which they designed and installed as they went along. There are 3-way switches at the top and bottom of the staircases. The second staircase was just as challenging as the first one.
The rocks have not been polished smooth and some still have lichen attached to represent the most natural appearance. According to Jimmy, the materials in his mountaintop retreat are: “All God made except stainless steel and glass.”

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