Can I Build Second Story Addition in Indianapolis, IN? (2026)
Find out if you can build a second story addition in Indianapolis, IN. Rules, permit requirements, costs, and next steps.
Adding a second story in Indianapolis, IN is possible in most zones, subject to height limits and structural permit requirements.
A second story addition is one of the most complex home improvement projects in Indianapolis, IN. It requires a full building permit, structural engineering review, and must comply with the height limits for your zoning district. Unlike a ground-floor addition, a second story changes the roofline and structural load path of your entire home, triggering stricter engineering requirements. In Indianapolis, zone height limits range from 35 feet in D-1 zones — verify your zone before planning.
Second Story Addition Rules in Indianapolis
Second Story Addition Rules in Indianapolis: Building permit required: Yes — all second story additions require a permit. Permit thresholds: All structural additions to primary dwelling. Example height limit (D-1): 35 feet, max 2 stories. Structural engineering drawings required. Setbacks apply to the full structure height. Indianapolis-Marion County DMD permit. Impervious cover calculation required. Floodplain review for properties near White River, Fall Creek, or other Indianapolis waterways.
Costs & Fees
Second story addition permit fees in Indianapolis: Based on value — typically $1,000–$4,000. Note: structural engineering fees ($2,000–$10,000+) are separate from permit fees.
Timeline
Plan check: 3-6 weeks. Construction typically 3-6 months for a full second story.
Next Steps
Next steps for adding a second story in Indianapolis: 1. Hire a structural engineer to assess your existing foundation and framing capacity. 2. Confirm your zone height limit and verify the addition meets all setback requirements. 3. Submit full structural plans and permit application to the Indianapolis Department of Metropolitan Development (DMD) — Building Permits. 4. Inspections required at foundation reinforcement, framing, shear panels, and final.
Indianapolis Department of Metropolitan Development (DMD) — Building Permits
Phone: (317) 327-5136
Website: https://www.indy.gov/activity/building-permits
Online Permits: https://www.indy.gov/activity/building-permits
Frequently Asked Questions
Can I build an ADU (carriage house or garage apartment) on my Indianapolis property?
Yes. Indianapolis-Marion County Unified Development Ordinance (UDO) allows accessory dwelling units — commonly called carriage houses or garage apartments — on single-family lots. Detached ADUs up to 900 sqft. No owner-occupancy requirement. No impact fees — permit costs are among the lowest of major US cities. One parking space required per ADU. Alley-access lots in historic neighborhoods like Old Northside and Irvington are particularly well-suited for carriage house ADUs. Permits through Indianapolis DMD.
What is Unigov and how does it affect my permits and zoning?
Unigov is Indianapolis's unique consolidated city-county government structure, established in 1970 by the Unigov Act. It merged Indianapolis city government with Marion County government into a single metropolitan government. For zoning and building permits, this means the Indianapolis Department of Metropolitan Development (DMD) administers the Unified Development Ordinance (UDO) for virtually all of Marion County — not just the old city limits. Most Marion County residents use the same DMD permit office and UDO rules. Exceptions include the excluded cities of Beech Grove, Lawrence, Southport, and the town of Speedway, which have their own local governments.
Are short-term rentals (Airbnb) allowed in Indianapolis?
Yes, without a primary-residence requirement — a significant difference from many cities. Indianapolis requires STR registration ($125/year) with DMD. No nightly cap. Designated local contact required for 24/7 complaint response. Indiana Hotel/Motel Tax (7%) plus Marion County Innkeeper's Tax applies. Insurance minimum of $500,000 required. Indianapolis is a major convention and sporting events city (Colts, Pacers, Indianapolis 500, Big Ten tournaments) — STR demand is strong particularly during major events at Lucas Oil Stadium and Gainbridge Fieldhouse.
What historic districts exist in Indianapolis and what do they require?
Indianapolis has several locally designated historic districts including the Old Northside Historic District (Victorian-era homes northeast of downtown), Lockerbie Square (one of Indianapolis's oldest neighborhoods, brick cottages), Irvington Historic District (late 19th century suburb, National Register listed), and the Meridian Street Preservation District (grand boulevard with mansion-scale homes). The Indianapolis Historic Preservation Commission (IHPC) reviews all exterior alterations in designated areas. Certificate of Appropriateness (CoA) required before DMD issues building permits. Monthly IHPC public hearings at City-County Building.
How does Indianapolis's Indiana Cottage Food Law compare to other states?
Indiana has one of the more generous cottage food laws in the Midwest. The $50,000 annual revenue cap is higher than Ohio ($35,000), Pennsylvania ($35,000), and Michigan (no cap but more restrictions). No state permit or registration required for operations under the cap — just the required product labeling. Indianapolis City Market and Broad Ripple Farmers Market are major venues for cottage food sellers. The law covers baked goods, jams, jellies, candy, dried herbs, and has been expanded to include some refrigerated items sold immediately. Full text at Indiana Code Section 16-42-5.2.
What are the flood risk areas in Indianapolis and how does it affect development?
Indianapolis has significant flood risk areas along the White River, Fall Creek, Eagle Creek, and several smaller creek systems. The White River bisects the city from north to south. Properties in FEMA Special Flood Hazard Areas (Zone AE) require flood insurance and must meet Indianapolis floodplain management standards. New construction in flood zones must have finished floor elevation at least 1 ft above 100-year flood elevation. Indianapolis has invested in flood control after historic flooding events. The Marion County floodplain map and FEMA Flood Map Service Center are the definitive sources for your property's flood zone status.
Source: Indianapolis Department of Metropolitan Development (DMD) — Building Permits — Building Regulations. Last verified April 6, 2026. View source