Glossary

Setback (Building Setback Line)

Also known as: Yard Requirement, Building Setback Line

The minimum required horizontal distance between a building or other structure and a lot line — front, side, and rear — within which no structure may be built, establishing the outer boundary of a parcel's buildable envelope.

Setbacks work in combination with height limits, floor area ratio, and lot coverage maximums to define a site's buildable envelope — the three-dimensional volume within which a building may actually be constructed — and it is common for a site to be constrained by one of these factors well before the others are reached, meaning maximizing buildable area requires testing setbacks against height and FAR simultaneously rather than assuming FAR alone determines the achievable building size. Setback requirements frequently vary by frontage type (a corner lot typically carries two front setbacks rather than one front and one side), by adjacency (a rear setback abutting a residential district is often larger than one abutting another commercial parcel), and by building element, since some codes allow specific projections to encroach into a required setback within defined limits. Many urban infill and form-based codes have moved toward build-to lines — a required minimum and maximum setback, rather than a simple minimum — specifically to prevent suburban-style building placement behind surface parking in favor of a consistent street wall, which is a materially different design objective than a conventional suburban setback regime.