Chelsea, MA Building Setbacks & Zoning: Setback Rules (2026)

Chelsea's dimensional regulations article opens with Sec. 34-76, which requires every structure, use and lot to conform to the table of dimensional regulations in Sec. 34-262 unless the chapter or a state statute exempts it, and limits a lot to one principal structure except where the chapter says otherwise. Subsection (c) locks in existing nonconforming yards: a yard or lot that already existed when the current zoning ordinance passed cannot be reduced below the code's minimums, and any yard or lot created after that date has to meet the minimums from the start.

The specific side yard numbers for the R1, R2 and R3 residential districts come from Sec. 34-78(e), Required yards in R1, and R2 and R3 districts, whose second paragraph sets the standard directly: the combined width of the two side yards cannot be less than 20 feet in the R1 district or 12 feet in the R2 district, and no single side yard in either district can be less than five feet. The same subsection also lets a builder average the front-yard setback of two neighboring lots when placing a new dwelling between them, subject to sign-off from the inspectional services and planning and development departments.

Front, side and rear yard figures for every other district, including the Business, Retail Business, Waterfront, Port and Industrial districts, are set out numerically in the table of dimensional regulations referenced at Sec. 34-262 rather than written out in article IV's text. Sec. 34-78(h) separately requires that a Shopping Center or Industrial district lot adjoining a residential district match whatever yard the adjoining residential district requires, front, side or rear.