Do I need a permit for a full bathroom remodel in
Sedalia, Missouri?

Sedalia bathroom remodel permits — the key details

Permit requirement hinges on what you're actually changing. Per IRC R307 and Sedalia's adoption of the Missouri State Building Code, any relocation of a plumbing fixture (toilet, sink, tub, shower drain) requires a permit and inspection. The most common trigger is moving a toilet to a new location—even 2 feet over—because the trap arm (the horizontal drain line from the toilet to the vent stack) has a maximum length of 6 feet per IRC P3005.1, and if your bathroom layout is tight or the main vent is far away, you'll need a plan showing how the new drain routing meets that limit. Similarly, if you're converting a tub to a shower (or vice versa), you need a permit because the waterproofing assembly changes: a shower enclosure requires a continuous, sloped membrane system per IRC R702.4.2 (cement board + liquid membrane, or a pre-formed membrane system), whereas a tub surround may have different backing requirements. Sedalia's building inspectors verify this on the rough-in, so you must have a detail drawing showing the waterproofing method—not just 'we'll use Schluter' but specifically what goes behind the tile and how water is directed to the drain. Plumbing fixture replacement in the same location (same drain, same supply lines) does not require a permit; swapping out a faucet, replacing a cracked toilet, or removing and re-setting a vanity in its original footprint are all exempt. Exhaust fan installation is the other major trigger: if you're adding a new exhaust fan or moving an existing one, you need a permit to show compliance with IRC M1505, which requires the exhaust duct to terminate outside the home (not into an attic, not into a soffit without a damper) and requires 6 inches of insulated duct per the code. Sedalia inspectors are strict on this because moisture damage in attics is common in the 4A climate zone, and improper ductwork leads to mold claims.