ADU Rules in Nashville, TN (2026)
ADU rules, permit requirements, size limits, and fees for Nashville, TN. Source-cited from official municipal code.
Yes, ADUs are allowed in Nashville, TN.
Nashville, TN permits accessory dwelling units (ADUs) on residential properties. ADUs — also called granny flats, in-law units, backyard cottages, or secondary suites — are secondary housing units on a single-family or multifamily lot. State and local law governs the approval process. In Nashville, the Metro Nashville Department of Codes Administration handles ADU permit applications. Below you will find the current size limits, setbacks, fees, and timeline for building an ADU in Nashville.
ADU Size Limits
ADU Size Limits in Nashville: Detached ADU: up to 1000 sq ft (max height: 25 feet). Attached ADU: 40% of primary dwelling floor area. Metro Nashville Code Title 17. Detached Accessory Dwelling Units (DADUs) allowed up to 1,000 sqft in qualifying residential zones. JADU is a California-specific concept not used in Tennessee zoning terminology.
| Type | Max Size | Max Height |
|---|---|---|
| Detached ADU | 1000 sq ft | 25 feet |
| Attached ADU | 40% of primary dwelling floor area | Per zone height limit |
Permit Fees
ADU Permit Fees in Nashville: Plan check fee: $200–$1,200. Building permit fee: Based on construction value — typically $800–$3,500. Impact fees: Metro Nashville charges development fees — water and wastewater tap fees apply for new connections. School fees: None or N/A. Total estimated permit cost: $2,000–$9,000 total fees. Metro Nashville water and wastewater tap fees apply for new utility connections for a DADU with independent plumbing. Fee schedule: https://www.nashville.gov/departments/water-services
| Fee Type | Amount |
|---|---|
| Plan Check | $200–$1,200 |
| Building Permit | Based on construction value — typically $800–$3,500 |
| Impact Fees | Metro Nashville charges development fees — water and wastewater tap fees apply for new connections |
| School Fees | None |
| Total Estimate | $2,000–$9,000 total fees |
Permit Timeline
Nashville ADU Permit Timeline: Metro Nashville Codes permit: typically 3-6 weeks for residential projects. Electronic permit review available. Construction typically 4-12 months. Apply through the Metro Nashville Department of Codes Administration online permit portal. Phone: (615) 862-6500.
Setback Requirements
ADU Setback Requirements in Nashville: Front setback: follows zone standard. Side setback: 5 feet. Rear setback: 5 feet. Detached ADUs in Nashville must maintain minimum 5 ft rear and side setbacks. Alley-facing properties may place ADU near alley. Metro Nashville Code Title 17.
Parking Requirements
Parking Requirements: 1 parking space required per DADU. Nashville does not have a public transit system equivalent to BART or CapMetro that would justify significant parking waivers.
Restrictions & Requirements
- DADU must be on same lot as primary single-family dwelling
- Maximum 1 DADU per single-family lot
- Maximum size: 1,000 sqft
- Must comply with RS zone setback and lot coverage standards
- DADU cannot be separately sold or conveyed
- Access easement or alley access preferred for rear-yard DADUs
How Many ADUs Are Allowed?
Number of ADUs Allowed in Nashville: Single-family lots: 1 DADU per single-family lot. Multifamily properties: Not typically allowed as separate accessory units in RM zones. Nashville allows one Detached Accessory Dwelling Unit per single-family lot in qualifying residential zones (RS5, RS7.5, RS10, RS15 and similar). Attached accessory dwelling units may also be allowed in some configurations.
Single-Family Lots
1 DADU per single-family lot
Multifamily Properties
Not typically allowed as separate accessory units in RM zones
Historic District Considerations
Historic District Requirements: Nashville has 18 historic districts where additional design review may be required for ADU construction. Design review approval is required before obtaining a building permit for properties in historic overlay zones. Metro Nashville Historical Commission designates Nashville Historic Landmarks and oversees Historic Overlay (H Overlay) districts including Germantown, Edgefield, Lockeland Springs, East End, Waverly-Belmont, and others. Certificate of Appropriateness required for exterior changes to designated properties and structures in H Overlay districts. Nashville has significant historic resources from multiple eras. Look up historic district boundaries at: https://www.nashville.gov/departments/historical-commission
Frequently Asked Questions
Can I build an ADU in Nashville?
Yes. Nashville, TN allows accessory dwelling units. On a single-family lot you can build 1 DADU per single-family lot.
How big can an ADU be in Nashville?
The maximum size for a detached ADU in Nashville is 1,000 square feet.
How long does it take to get an ADU permit in Nashville?
The typical ADU permit timeline in Nashville is Metro Nashville Codes permit: typically 3-6 weeks for residential projects. Electronic permit review available. Construction typically 4-12 months.. Total estimated permit fees are $2,000–$9,000 total fees.
Do I need extra parking for an ADU in Nashville?
No, Nashville does not require additional parking for ADUs.
Do I have to live on-site to have an ADU in Nashville?
No, owner-occupancy is not required for ADUs in Nashville.
Source: Metro Nashville Code Title 17 — Zoning; DADU (Detached Accessory Dwelling Unit) provisions. Last verified April 5, 2026. View source