The split-level—more precisely, the bi-level—was a ubiquitous 1960s housing type, defined by its layered organization: bedrooms above the garage, living spaces over a partially daylit basement, and an entry set between them with half-flights of stairs. Expanding this typology is inherently complex, shaped by its compact structure, fixed stair locations, and low rooflines - challenges heightened here by the addition of a third story and the need to moderate the scale of a hilltop home for a family of five.

The design retains the underlying logic of the original split-level while fundamentally reworking the house. A new third floor accommodates the primary suite, relocating it from the basement. The main level is opened to form a continuous living, kitchen, and dining space. At one end, a vaulted ceiling extends toward a sheltered walk-out patio; at the other, a full-height wall of glazing frames distant water views. The enclosed stair is replaced with an open-riser steel and wood assembly, introducing light and visual continuity between levels. A patterned steel screen provides fall protection at the entry porch, stair, and upper deck while filtering daylight into adjacent interiors.

Materially, the exterior clarifies the building’s organization. Brick anchors the exposed lower levels, while a new hip roof with deep overhangs shelters the wood-clad upper story, reducing weathering and visually tempering the home’s increased scale.