Fair Lawn, NJ Accessory Structures: ADU Rules (2026)

Fair Lawn is a Bergen County borough of approximately 35,000 residents that operates under the NJ Municipal Land Use Law. Chapter 125 of the Borough Code (the 'Land Development Ordinance of Fair Lawn Borough') is the comprehensive zoning ordinance: it regulates and limits land uses; the use, location, height and bulk of buildings; yards and open space; and the density of population, dividing the Borough into districts shown on the Zoning Map. Article III (Zoning Regulations) sets the use schedule for each district. In the R-1-1, R-1-2 and R-1-3 Zones, a one-family dwelling is permitted with only one such dwelling per lot and no other principal use on the lot, plus accessory uses customarily incidental to and located on the same lot as the principal use. The R-2 Zone adds two-family dwellings on top of all R-1 uses; R-3-1 and R-3-2 add multiple-family dwellings. Article III's Supplementary Zoning Regulations require that accessory buildings, structures and uses be located only on the same lot as the principal building to which they are accessory, and that they comply with the bulk and area regulations of the underlying zone. Fair Lawn's code does not separately list an 'accessory dwelling unit', 'accessory apartment' or 'in-law suite' as a permitted accessory use, so creating a second independent dwelling on a one-family lot generally requires a use variance from the Zoning Board of Adjustment under N.J.S.A. 40:55D-70(d). Construction is governed by the NJ Uniform Construction Code (N.J.A.C. 5:23) administered by the Fair Lawn Construction Code Official; zoning approval comes from the Borough Zoning Officer. As of 2026, NJ has no statewide ADU mandate.