Jackson County, MS Accessory Structures: ADU Rules (2026)

Jackson County addresses accessory dwelling units through local zoning in Pascagoula, Ocean Springs, Moss Point, Gautier, Vancleave, and unincorporated county areas. Mississippi does not have statewide ADU legislation like California or Oregon, so all regulations are local under MS Code Ann. §17-1-1 zoning authority. Some Jackson County municipalities permit ADUs in certain residential zones through conditional use permits requiring public hearings and neighbor notification. Common requirements include maximum size limits (typically 600 to 1,000 square feet or a percentage of the primary dwelling), owner-occupancy of either the primary or accessory unit, separate utility connections or submeters, and one to two off-street parking spaces. ADUs must meet the adopted International Residential Code for habitable space, including ceiling height (7 feet minimum), egress windows, insulation, and electrical standards. Gulf Coast flood zone requirements apply, meaning ADUs in Special Flood Hazard Areas must have finished floors above base flood elevation, often on pilings or elevated foundations common in coastal Jackson County. Setbacks typically require 3 to 10 feet from property lines depending on zone. Manufactured housing and mobile homes used as ADUs may face additional restrictions under local zoning. Mississippi's growing interest in affordable housing and aging-in-place options is driving gradual acceptance of ADU-friendly policies, though adoption remains slow compared to coastal states. Post-Katrina rebuilding in some Jackson County neighborhoods demonstrated the utility of compact accessory units.