Setback (architecture)

A setback, in the specific sense of a step-back, is a step-like form of a wall or other building frontage, also termed a recession or recessed story.^[1] Importantly, one or more step-backs lowers the building's center of mass, making it more stable. A setback as a minimum one-bay indent across all stories is called a recessed bay or recess and is the more common exterior form of an alcove.

Notable upper stories forming a step-back may form a belvedere – and in residential use are considered the penthouse. If part of the roof, then they are a loft or attic/garret.