For years, Antje Bulthaup, an architectural designer, had her eye on a house with a fusty beauty salon on the ground floor and a two-storey residence on top. When the owner decided to sell, she pounced. “Since I’d dreamed about this building for so long, I was full of visions for it,” she says. During a 14-month reno, her crew ripped the main floor down to the studs. Bulthaup brought in Douglas fir planks from Denmark for flooring and designed oak-framed windows to swallow up the sun—perfect for the space’s reincarnation as a yoga studio.