Non-conforming plots in Marblehead

Most homes in Marblehead do not comply with the zoning that governs them. This map shows the residential lots that are pre-existing nonconforming, typically undersized lots or houses inside a modern setback line, none of which broke any rule when they were built. Under the town's ADU bylaw, that status triggers an extra discretionary finding, which means the state's by-right ADU law effectively stops at the property line for a majority of Marblehead homeowners.