Chelsea, MA Building Setbacks & Zoning: Structure Height Limits (2026)

)' by district: the R-1 district (one- and two-family homes) and the R-2 district (one- to three-unit buildings) are both capped at 35 feet, with a matching 'Maximum number of stories' limit of three stories in each district. Section 34-78(j) then defines what does not count against that limit: belfries and towers built exclusively for ornamental purposes, flagstaffs, chimneys, flues, electric generating plants, passive solar devices, elevator shafts, water tanks, standpipes, bulkheads, headhouses for roof access, roof deck railings, and mechanical equipment are all exempt from the height regulations, and parapet walls or cornices may extend up to three feet above the height limit without counting as a violation.

Because Chelsea sits directly across the Mystic River from Logan Airport's approach paths, Section 34-78(j)(2) layers a separate, overriding limit on top of the zoning table: the code directs applicants to the Federal Aviation Regulations at 14 CFR Part 77 governing objects affecting navigable airspace, and states flatly that no structure may be erected or maintained in any district to a height in excess of whatever limit those federal regulations establish, regardless of any other provision of the zoning chapter. Outside the R-1 and R-2 districts, several nonresidential and mixed-use districts allow greater heights by special permit, and Section 34-80(1) specifically lets the zoning board of appeals authorize heights above the table's listed maximum, up to 80 feet, in the Highway Business, Light Industrial, and Industrial districts after site plan approval, but no comparable special-permit path raises the 35-foot cap in the core R-1 or R-2 residential districts.