What flooring would you lay in a bank vault? That's the question OPN Architects in Madison, Wis., asked when they designed a three-floor pizzeria in a triangular building that, almost 100 years ago, began as a bank. The 450-square-foot vault in the basement is narrow, so OPN and Appleton, Wis.-based Urban Evolutions, the material supplier and design partner, chose wood to dampen the echo within the steel vault and a chevron pattern to pull patrons into the space. The flooring angle also makes the room feel wider than it appears, said Kenn Hensrud, owner of K.O.H. Wood Flooring of Oneida, Wis. His company glued and nailed the flooring—2¼-inch-wide reclaimed oak—on top of plywood that they fastened to the vault's steel surface with machine screws. The floor was hard-plated to keep its worn patina intact and then coated with a waterborne matte finish. Was this one of the more unique locations where Hensrud has ever installed flooring? You can bank on it.