The Larger Bathroom Reduced Hallway Function

The 4-inch cast iron plumbing stack ran through the bathroom's shared wall with the hallway. Because the stack also served the upstairs bathroom, relocating it would have required cutting into the floor joists on both levels and rerouting the drain line through the basement—an estimated $12,000 expense that the homeowners rejected.

With the stack immovable, the only direction the bathroom could expand was into the hallway. The original hallway was 42 inches wide, well above the 36-inch minimum for residential corridors. After the two-foot expansion, the hallway narrowed to 30 inches at the pinch point where the vanity protruded. While this still met the building code minimum of 30 inches for non-accessible corridors, it failed the practical test: two adults could not pass each other, and moving a queen-size mattress through the hallway required tilting it sideways.

The design team ultimately addressed the issue by recessing the vanity cabinet 18 inches into the wall at the pinch point, creating a niche that restored the hallway to 36 inches at the critical passing zone. The niche was framed with the same tile as the bathroom, making it feel like an intentional alcove rather than a concession.