The top floor of Gavin and Sheila Smith’s century-old Craftsman-style house in Seattle’s Queen Anne neighborhood was, by any measure, a lousy place to sleep and keep an office. “It was cold, it was dark, it was cramped, it was just barely functional,” Gavin says. So, in 2012, Gavin, an architect, set about transforming it into a lightfilled suite that includes a master bedroom and bathroom and a versatile space where he and his family could work and play.
His first step was to remove a series of collar ties to create a cathedral ceiling, which added nearly three feet of headroom at the center. A brick chimney was demolished, and four skylights were installed. In the office, Gavin designed built-ins—cabinets, a pair of desks, and two daybeds where the…