ADU Rules in Chattanooga, TN (2026)
ADU rules, permit requirements, size limits, and fees for Chattanooga, TN. Source-cited from official municipal code.
Yes, ADUs are allowed in Chattanooga, TN.
Chattanooga, 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 Chattanooga, the Chattanooga Department of Development Resources handles ADU permit applications. Below you will find the current size limits, setbacks, fees, and timeline for building an ADU in Chattanooga.
ADU Size Limits
ADU Size Limits in Chattanooga: Detached ADU: up to 800 sq ft (max height: 20 feet). Attached ADU: 35% of primary dwelling floor area. Chattanooga City Code accessory dwelling unit provisions. Detached ADUs limited to 800 sqft in R-1 and R-2 residential zones. JADU is a California-specific concept not applicable in Tennessee.
| Type | Max Size | Max Height |
|---|---|---|
| Detached ADU | 800 sq ft | 20 feet |
| Attached ADU | 35% of primary dwelling floor area | Per zone height limit |
Permit Fees
ADU Permit Fees in Chattanooga: Plan check fee: $100–$600. Building permit fee: Based on construction value — typically $500–$2,200. Impact fees: Chattanooga charges utility connection fees through EPB and AWWA. School fees: None or N/A. Total estimated permit cost: $1,200–$5,500 total fees. Chattanooga's permit fees are moderate for a mid-size Tennessee city. EPB (Electric Power Board) and Chattanooga Water connection fees apply for new utility services.
| Fee Type | Amount |
|---|---|
| Plan Check | $100–$600 |
| Building Permit | Based on construction value — typically $500–$2,200 |
| Impact Fees | Chattanooga charges utility connection fees through EPB and AWWA |
| School Fees | None |
| Total Estimate | $1,200–$5,500 total fees |
Permit Timeline
Chattanooga ADU Permit Timeline: Chattanooga Development Resources permit: typically 3-6 weeks for residential permits. Construction typically 4-12 months. Apply through the Chattanooga Department of Development Resources online permit portal. Phone: (423) 643-5902.
Setback Requirements
ADU Setback Requirements in Chattanooga: Front setback: follows zone standard. Side setback: 5 feet. Rear setback: 5 feet. Chattanooga City Code ADU setbacks. Minimum 5 ft rear and side setbacks for detached ADUs. Chattanooga's terrain creates irregular lot shapes in many neighborhoods.
Parking Requirements
Parking Requirements: 1 parking space required per ADU. Chattanooga has limited public transit — CARTA (Chattanooga Area Regional Transportation Authority) and the free electric shuttle downtown. Parking waivers rare outside downtown.
Restrictions & Requirements
- ADU must be on same lot as primary single-family dwelling
- Minimum lot size requirements by zone
- ADU cannot be separately conveyed from primary lot
- Total lot coverage including ADU must meet zone limits
- Chattanooga STR registration required if ADU is used for short-term rental
- Must comply with Tennessee Residential Code
How Many ADUs Are Allowed?
Number of ADUs Allowed in Chattanooga: Single-family lots: 1 ADU per single-family lot in qualifying R zones. Multifamily properties: Additional units may be allowed by right in R-3 and R-4 zones. Chattanooga allows one accessory dwelling unit per single-family lot. The city's growing appeal to remote workers and outdoor recreation enthusiasts has increased interest in ADU investment.
Single-Family Lots
1 ADU per single-family lot in qualifying R zones
Multifamily Properties
Additional units may be allowed by right in R-3 and R-4 zones
Historic District Considerations
Historic District Requirements: Chattanooga has 10 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. Chattanooga has historic resources in Fort Wood (Victorian neighborhood near UTC), Ferger Place, and portions of North Chattanooga. The Chattanooga Choo Choo terminal is a National Historic Landmark. Design review may apply for exterior changes to contributing structures in locally designated historic districts. Contact Development Resources for specific designations. Look up historic district boundaries at: https://www.chattanooga.gov/development-resources/historic-zoning
Frequently Asked Questions
Can I build an ADU in Chattanooga?
Yes. Chattanooga, TN allows accessory dwelling units. On a single-family lot you can build 1 ADU per single-family lot in qualifying R zones.
How big can an ADU be in Chattanooga?
The maximum size for a detached ADU in Chattanooga is 800 square feet.
How long does it take to get an ADU permit in Chattanooga?
The typical ADU permit timeline in Chattanooga is Chattanooga Development Resources permit: typically 3-6 weeks for residential permits. Construction typically 4-12 months.. Total estimated permit fees are $1,200–$5,500 total fees.
Do I need extra parking for an ADU in Chattanooga?
No, Chattanooga does not require additional parking for ADUs.
Do I have to live on-site to have an ADU in Chattanooga?
No, owner-occupancy is not required for ADUs in Chattanooga.
Source: Chattanooga City Code — Accessory Dwelling Unit and Zoning provisions. Last verified April 6, 2026. View source