Stairs can often consume large volumes of space, which is especially problematic in a narrow house as in this San Francisco victorian remodel. This stair creates a continuous surface that connects the critical spaces on the home’s three floors as it twists through the main atrium. It was equally important that the stair would avoid blocking any of the light or fill the hard-won space that created the overall open feeling in the house. This duality of presence and transparency was the impetus for using perforated plate folded into a seamless run from the basement to the top floor.

The perforated plate literally folds around the plate ribs and is welded in place. The plate is spot welded to the ribs as discretely as possible, creating an impression of a single object. The fold of the tread extends to become the guardrail. By folding the guardrail around the landings and the floors a continuous vertical path was created, inviting and definitive throughout the space. .