Do I need a permit for interior remodeling in Unincorporated Orange County?

It depends. Whether interior remodeling needs a permit in Unincorporated Orange County comes down to the details of your project.

A remodel that moves walls or includes electrical, plumbing, or mechanical work falls outside cosmetic exemptions, which cover finishes such as paint, flooring, trim, and cabinets. Each trade normally needs its own permit and inspection on top of the building permit, and removing or altering a load bearing wall usually requires a beam detail or engineering before the work is approved. Opening walls in an older home can trigger separate lead paint, asbestos, and smoke alarm requirements, so raise those with your department at application time. Indiana's residential code deletes the IRC's permit, exemption, inspection, and fee sections (R105 and R108 to R114), so whether this job needs a permit is set by the local ordinance of the city, town, or county, not by the model IRC exemption list. Under Indiana's R314.2.2 and R315.2.2, alterations requiring a permit trigger smoke and carbon monoxide alarms as for new dwellings, except electrical work in existing rooms other than new or relocated bedrooms. Additions and alterations must meet the code for new work without requiring the whole existing house to be brought up to current code, and must not make the existing structure unsafe (Indiana's substitute Section R105).