Accessory Structures in New Brunswick, NJ: What Residents Actually Need to Know

If you live in New Brunswick or are thinking about moving there, accessory structures are one of those things you probably won't think about until they affect you directly. New Brunswick has 3 specific rules on the books covering different aspects of accessory structures, and some of them might surprise you.

Shed Rules

Accessory structures require permits under N.J.A.C. 5:23 (NJ UCC). Structures under 200 sq ft on skids may be exempt in some NJ municipalities. Setbacks governed by New Brunswick Title 17 zoning.

Key details: State Code: N.J.A.C. 5:23 (NJ UCC). Possible Exemption: Under 200 sq ft on skids (verify locally). Setbacks: Per New Brunswick Title 17 zoning. Contact: New Brunswick Construction Department.

Unpermitted structure: retroactive permit with penalty. Setback violation: modification or removal. Habitation: immediate correction.

Garage Conversions

Garage conversions require building permits under N.J.A.C. 5:23 and must comply with New Brunswick's zoning code. May qualify as an ADU under the 2024 NJ ADU mandate.

Key details: Permit Required: Yes — N.J.A.C. 5:23. ADU Option: May qualify under N.J.S.A. 52:27D-123.16. Zoning: Must comply with Title 17. Contact: New Brunswick Construction Department.

Unpermitted conversion: code enforcement. Must bring to code or restore. Safety violations: immediate correction required.

ADU Rules

New Jersey's ADU mandate (N.J.S.A. 52:27D-123.16, 2024) requires New Brunswick to allow ADUs by right on lots with single- or two-family homes. Owner-occupancy cannot be required. Min ADU size 850 sq ft cannot be restricted.

Key details: State Mandate: N.J.S.A. 52:27D-123.16 (2024). ADUs Required: By right on SF/2-family lots. Owner Occupancy: Cannot be required. Min ADU Size: Cannot restrict below 850 sq ft.

Unpermitted ADU: code enforcement. Zoning violation: $100 to $2,000/day. May require removal of unpermitted unit.

The rules around adu rules in New Brunswick lean permissive, but that does not mean anything goes.

The Bottom Line

New Brunswick's accessory structures rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming New Brunswick is broadly strict or permissive.

These rules come from New Brunswick's publicly available municipal code. For complete penalty schedules, exemption details, and answers to common questions, see the individual ordinance pages throughout this guide.