ADU Rules in Louisville, KY (2026)
ADU rules, permit requirements, size limits, and fees for Louisville, KY. Source-cited from official municipal code.
Yes, ADUs are allowed in Louisville, KY.
Louisville, KY 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 Louisville, the Louisville Metro Planning and Design Services handles ADU permit applications. Below you will find the current size limits, setbacks, fees, and timeline for building an ADU in Louisville.
ADU Size Limits
ADU Size Limits in Louisville: Detached ADU: size varies by zoning — see official source (max height: varies — see official source). Attached ADU: size varies by zoning — see official source.
| Type | Max Size | Max Height |
|---|---|---|
| Detached ADU | See official source | See official source |
| Attached ADU | See official source | See official source |
Permit Fees
ADU Permit Fees in Louisville: Plan check fee: Varies. Building permit fee: Varies. Impact fees: None. School fees: None or N/A. Total estimated permit cost: Varies.
| Fee Type | Amount |
|---|---|
| Plan Check | See official source |
| Building Permit | See official source |
| Impact Fees | See official source |
| School Fees | None |
| Total Estimate | See official source |
Permit Timeline
Louisville ADU Permit Timeline: Louisville Metro Planning and Design Services permit: typically 4-8 weeks for residential permits. Online permitting through Louisville Metro government portal. Construction typically 4-14 months. Apply through the Louisville Metro Planning and Design Services online permit portal. Phone: (502) 574-3131.
Setback Requirements
ADU Setback Requirements in Louisville: Front setback: follows zone standard. Side setback: no minimum. Rear setback: no minimum.
Parking Requirements
Parking Requirements: 1 parking space required per ADU. Louisville is auto-dependent — TARC (Transit Authority of River City) bus service is available but limited. No parking waivers for transit proximity in most residential zones.
Restrictions & Requirements
How Many ADUs Are Allowed?
Number of ADUs Allowed in Louisville: Single-family lots: 1 ADU per single-family residential lot. Multifamily properties: Multiple units allowed by right in R-5 through R-8 zones. Louisville Metro allows one accessory dwelling unit per single-family lot. The 2003 city-county consolidation eliminated jurisdictional boundary issues for ADU development within Jefferson County.
- Single-Family Lots
- See official source
- Multifamily Properties
- See official source
Statewide Preemption
ADU Preemption
We could not confirm a statewide ADU preemption statute for Kentucky.
View Kentucky preemption detailsHistoric District Considerations
Historic District Requirements: Louisville has 22 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. Louisville has exceptional historic resources. Old Louisville (south of downtown) is the largest preserved Victorian neighborhood in the US — over 1,400 Victorian-era structures in approximately 45 blocks. Butchertown, St. James-Belgravia, and NuLu have locally designated historic districts. Louisville Landmarks Commission designates local landmarks and oversees design review for H overlay zones. Certificate of Appropriateness required for exterior changes to designated properties. Look up historic district boundaries at: https://louisvilleky.gov/government/office-planning
Frequently Asked Questions
Can I build an ADU in Louisville?
Yes. Louisville, KY allows accessory dwelling units. On a single-family lot you can build 1 ADU per single-family residential lot.
How big can an ADU be in Louisville?
The maximum size for a detached ADU in Louisville is 900 square feet.
How long does it take to get an ADU permit in Louisville?
The typical ADU permit timeline in Louisville is Louisville Metro Planning and Design Services permit: typically 4-8 weeks for residential permits. Online permitting through Louisville Metro government portal. Construction typically 4-14 months.. Total estimated permit fees are $2,000–$8,000 total fees.
Do I need extra parking for an ADU in Louisville?
Louisville parking rules for ADUs: 1 parking space required per ADU. Louisville is auto-dependent — TARC (Transit Authority of River City) bus service is available but limited. No parking waivers for transit proximity in most residential zones.
Do I have to live on-site to have an ADU in Louisville?
Owner-occupancy requirement in Louisville: Louisville Metro does not impose owner-occupancy requirements for ADU approval. Both the primary unit and ADU may be independently rented.
Source: Louisville Metro Land Development Code (LDC) — Accessory Dwelling Unit provisions. Last verified April 6, 2026. View source