Everything homeowners ask about building an ADU in Nashville — answered with 2026 data.
Yes, ADUs are allowed in RS (single-family) with DADU overlay; R or RM zones with alley access or UDO; Urban Services District; General Services District with DADU overlay in Nashville, TN. The maximum size for a detached ADU is 1200 sq ft (but must not exceed footprint of primary structure). Attached ADUs can be up to Limited; must be subordinate to primary dwelling. Nashville has an ADU-friendliness score of 7/10. Check our full Nashville ADU rules page for complete zoning details.
ADU construction in Nashville typically costs $150,000-$250,000. The cost per square foot averages $225-$350. Garage conversions are more affordable at $100,000-$180,000, while prefab ADUs cost $80,000-$140,000. Permit fees add $2,500-$5,000 estimated (permit fees + covenant recording) to your budget. See our detailed Nashville ADU cost guide.
Detached ADUs in Nashville can be up to 1200 sq ft (but must not exceed footprint of primary structure). Attached ADUs are limited to Limited; must be subordinate to primary dwelling. Junior ADUs (JADUs) have a cap of N/A (Nashville uses DADU terminology). Maximum height is Must be subordinate to primary dwelling; typically 1-2 stories. You are allowed up to 1 DADU per lot (with conditions) on a qualifying lot.
Rear setback: 5 ft minimum. Side setback: 5 ft minimum. Front setback: 10 ft minimum separation from primary dwelling (alley edge consideration). Note that garage conversions may be exempt from setback requirements if the existing structure is already within the setback area.
Typically included on-site. Many cities and states have been relaxing ADU parking requirements in recent years. In California, no additional parking is required for ADUs near transit.
Required - owner must live in primary dwelling or DADU. Note that owner-occupancy rules vary by state law — California and several other states have eliminated this requirement for standard ADUs.
The ADU permit review timeline in Nashville is typically 60-90 days typical; longer for Historic Overlay reviews. The plan check process takes approximately 3-4 weeks typical. Pre-approved plans availability: City has DADU design standards and guidelines.
Average ADU rental income in Nashville: 1-bedroom units rent for $1,200-$1,700/month, 2-bedroom units for $1,600-$2,200/month. Short-term rentals: Restricted under restrictive covenants; long-term only. Expected ROI: 7-10 year payback; $100K+ supplemental income over 5 years.
The minimum lot size for an ADU in Nashville is Varies by overlay district; typically 10,000 sq ft minimum for some areas. This applies to detached ADUs — garage conversions and JADUs may have different or no lot size requirements.
Garage conversions are one of the most popular and affordable ADU options. In Nashville, a garage conversion typically costs $100,000-$180,000. The key advantages are lower cost (no foundation work), potential setback exemptions, and faster permitting. Read our complete garage conversion guide.