ADU Rules in Huntsville, Alabama

Huntsville, one of Alabama's fastest-growing cities, permits accessory dwelling units (ADUs) in residential zones under its Zoning Ordinance. Alabama has no statewide ADU law, so Huntsville's local code governs all ADU development.

Permitted ADU Types

• Detached ADU: A separate structure on the same residential lot
• Attached ADU: Living space added to the primary dwelling with its own entrance
• Accessory Structure Conversion: Converting an existing garage or outbuilding to a dwelling unit

Size Limits

Setbacks

• Front setback: Must meet base zone standards (typically 25–35 ft)
• Side setback: 5 feet minimum
• Rear setback: 10 feet minimum
• Separation from primary: 10 feet between detached ADU and main structure

Height

• Detached ADU: 20 feet maximum
• Must not exceed height of primary dwelling

Owner Occupancy

The property owner must occupy either the principal residence or the ADU. Short-term rentals of ADUs may be subject to separate short-term rental ordinance requirements.

Parking

One additional off-street parking space is required per ADU. The space must meet minimum dimensions and surface standards.

Permit Process

1. Check zoning: Verify your district allows ADUs at the Huntsville Planning Department
2. Prepare plans: Submit site plan, floor plans, and elevations
3. Planning review: Staff reviews for zoning compliance
4. Building permit: Apply through Huntsville Permit Center
5. Inspections: Schedule required inspections at each phase
6. Final approval: Certificate of Occupancy upon completion

Contact

Huntsville Planning Department Huntsville City Hall, 308 Fountain Circle, Huntsville, AL 35801 Phone: (256) 427-5100 Website: huntsvilleal.gov/development/planning

Disclaimer: Regulations change. Verify current requirements with the Huntsville Planning Department before starting any project.