“We wanted the stair to be sculptural because it’s the first thing you see when you walk in the door, but it also has to lead you upstairs where the living spaces of the house are,” says Steven House of the multi-purpose stair design in this San Francisco home. He also used the stair sculpture to hide the air duct and provide seating adjacent to the built-in coat closet. The architect wanted to incorporate all of these elements into something dramatic despite the clients’ tight budget, so he focused on a big bang design implemented with straightforward materials. Clear maple for the coat closet-cum-guard rail contrasts with red oak stairs and flooring. Black painted 2x4s run horizontally between the cabinet and the extra wide baluster. “The horizontal boards mimic the grille lines,” says House, “but the black also almost disappears.” The third tread skips a step on the side to generate a comfortable sitting height of 20 inches while extending out past the handrail about 15 inches. It’s a great place to set your briefcase or yourself as you come in the door, adds House. Builder: Claxton Associates, Nevato, Calif.; Architect: House + House Architects, San Francisco; Photographer: Claudio Santini.