A Toronto family commissioned a 2,000-square-foot weekend retreat outside of the city on a hilly 100 acres where they bike and hike. Toronto-based Williamson Chong Architects divided the house into two volumes'a poured-in-place raw concrete base buried into the hill and oriented east and a rectangular volume, perched on top, oriented to the west.

Design concept and solution: The concrete base defines a “service bar” of rooms: the entry and stair, kitchen, office, bike garage, storage, and a mechanical room. Adjacent to that, a living room, with cedar-framed windows on three sides, offers panoramic views across the owners’ property. Polished concrete floors contain an efficient radiant-floor heating system.