Do I need a permit for basement finishing in Unincorporated Sherburne County?

Most likely yes. Basement finishing usually requires a permit in Minnesota. Confirm the specifics with Unincorporated Sherburne County.

Minnesota does not require an emergency escape opening when an existing basement is altered, but every new sleeping room created in an existing basement needs one unless the entire basement is sprinklered (Minn. R. 1309.0310). Finishing a basement under a building permit triggers smoke alarms and carbon monoxide alarms located as for new dwellings (Minn. R. 1309.0314 and 1309.0315). For permitted alterations, energy code insulation, air barrier, and vapor retarder requirements do not apply to existing basement walls of homes whose original permit was issued before June 1, 2009 (Minn. R. 1322.0100, subp. 3). Whether a building permit is issued at all depends on whether the city, township, or county covering the address has adopted and enforces the State Building Code (Minn. Stat. 326B.121); check the DLI local code lookup first. This basement project adds a bedroom, a bathroom or wet bar, or new electrical circuits, or moves the furnace or water heater. Finishing work of this kind normally needs a building permit and the matching trade permits. A basement bedroom needs an emergency escape and rescue opening, such as an egress window or door, which is one of the most common reasons basement work fails inspection. Plan for framing, electrical and plumbing rough-in inspections before insulation and drywall go up.