ADU Rules in Indianapolis, IN (2026)
ADU rules, permit requirements, size limits, and fees for Indianapolis, IN. Source-cited from official municipal code.
Whether ADUs are allowed in Indianapolis, IN has not been confirmed — see the official source before proceeding.
Whether Indianapolis, IN permits accessory dwelling units (ADUs) has not been confirmed from an official source. ADUs — also called granny flats, in-law units, or secondary suites — are secondary housing units on a single-family or multifamily lot. Contact the local building department through their official website to verify current ADU rules before proceeding, as regulations may have changed since this data was last reviewed.
ADU Size Limits
ADU Size Limits in Indianapolis: 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 Indianapolis: 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 | $150–$700 |
| Building Permit | $400–$2,500 based on construction value |
| Impact Fees | None |
| School Fees | None |
| Total Estimate | See official source |
Permit Timeline
Indianapolis ADU Permit Timeline: Permit timeline has not been confirmed — contact the department for current processing times. Apply through the local building department online permit portal. Contact them through their official website for current contact information.
Setback Requirements
ADU Setback Requirements in Indianapolis: Front setback: follows zone standard. Side setback: no minimum. Rear setback: no minimum.
Parking Requirements
Parking Requirements: Parking requirements have not been confirmed — see official source.
Restrictions & Requirements
- ADU must be on same lot as primary single-family or duplex dwelling
- Maximum one ADU per lot in D-1 through D-5 dwelling zones
- ADU cannot be separately sold or conveyed apart from primary lot
- Total impervious coverage limits apply per UDO zone requirements
- ADU must have independent entrance from primary dwelling
- Alley-access carriage houses must maintain 3 ft clearance from alley right-of-way
How Many ADUs Are Allowed?
Number of ADUs Allowed in Indianapolis: Single-family lots: not confirmed — see official source. Multifamily properties: not confirmed — see official source.
- Single-Family Lots
- 1
- Multifamily Properties
- Per D-6, D-7, D-8 zone density allowances
Statewide Preemption
ADU Preemption
We could not confirm a statewide ADU preemption statute for Indiana.
View Indiana preemption detailsFrequently Asked Questions
Can I build an ADU in Indianapolis?
Yes. Indianapolis, IN allows accessory dwelling units. On a single-family lot you can build 1.
How big can an ADU be in Indianapolis?
The maximum size for a detached ADU in Indianapolis is 900 square feet.
How long does it take to get an ADU permit in Indianapolis?
The typical ADU permit timeline in Indianapolis is Indianapolis-Marion County Department of Metropolitan Development (DMD) processes permits. Typical timeline: 3-6 weeks for zoning certification, 2-4 weeks for building permit. Indianapolis Access (indygo.indy.gov portal) available for online applications. Simple ADU/garage apartment projects may qualify for expedited review.. Total estimated permit fees are $700–$4,000 total fees.
Do I need extra parking for an ADU in Indianapolis?
Indianapolis parking rules for ADUs: 1 space per ADU required. Parking may be provided in driveway, garage, or off-street pad. Indianapolis is a car-dependent city — parking requirement reflects this. IndyGo bus transit serves limited neighborhoods — parking waiver not widely available.
Do I have to live on-site to have an ADU in Indianapolis?
Owner-occupancy requirement in Indianapolis: No owner-occupancy requirement under Indianapolis-Marion County UDO. Owners may rent both primary dwelling and ADU simultaneously.
Source: Indianapolis-Marion County Unified Development Ordinance (UDO) — Accessory Dwelling Unit Standards; Indiana Code Title 36-7. Last verified April 6, 2026. View source