Do I need a permit for accessory dwelling unit (adu) in Unincorporated Rush County?

Most likely yes. Accessory dwelling unit (adu) usually requires a permit in Indiana. Confirm the specifics with Unincorporated Rush County.

Since 2026, IC 36-7-1-1.5 defines an accessory dwelling unit as a self-contained living unit inside or on the same lot as a single family dwelling, no larger than the lesser of 75 percent of the home's interior habitable area or 1,000 square feet, with its own cooking, sleeping, and sanitation facilities, and complying with applicable building and safety codes. IC 36-7-4.3-3 requires each county, city, and town to hold a public hearing by January 1, 2027 to review its zoning with the goal of increasing housing, including accessory dwelling units; it calls for a review rather than requiring ADUs to be allowed on every lot, so zoning approval is still local. Under Indiana's Section R309.6, any habitable area in a detached garage or accessory structure must meet all applicable sections of the residential code and have an exit door or window as specified in Sections R310 and R311. The state does not issue permits for or inspect one- and two-family dwellings; if the local unit has no building permit ordinance, no state office issues one instead, but the 2020 Indiana Residential Code still applies to the work. A new accessory dwelling unit, detached or added on, is new residential construction. It normally needs a building permit with full plans, plus separate electrical, plumbing and mechanical permits, and zoning approval for a second unit on the lot. Utility connections (water, sewer or septic, and electric service) are usually reviewed as part of the permit, so ask about capacity and connection fees early.