Do I Need a Permit to Finish My Basement in Wisconsin?

Finishing a basement is considered a remodel under Wisconsin's Uniform Dwelling Code, and a building permit is required in every municipality. The permit ensures that the finished space meets code requirements for ceiling height (minimum 7 feet in habitable rooms), egress (at least one emergency escape window or door), moisture management, insulation, smoke and carbon monoxide detectors, and structural integrity of any framing modifications. In addition to the building permit, you will need an electrical permit for any new wiring — which is virtually guaranteed since a finished basement needs lighting, outlets, and smoke detector circuits. If you are adding a bathroom, a plumbing permit is required for the drain, water supply, and vent connections. If you are adding or modifying HVAC ductwork to heat and cool the basement, a mechanical permit may also be required. Total permit costs for a full basement finish in Wisconsin typically range from $300 to $1,200 across all required permits. Key code requirements for finished basements in Wisconsin include: habitable rooms must have a minimum ceiling height of 7 feet (beams and ducts can be lower if they do not reduce the clear height below 6 feet 4 inches over more than 50% of the room area); at least one egress window is required with a minimum opening of 5.7 square feet, a minimum width of 20 inches, and a maximum sill height of 44 inches above the floor (window wells are acceptable if they meet size requirements); all bedrooms need AFCI-protected circuits; and bathroom outlets must be GFCI-protected. Municipalities like Milwaukee and Madison have specific plan review processes for basement finishes. You will need to submit floor plans showing room layouts, egress window locations, electrical and plumbing plans, and HVAC modifications. Plan review typically takes 1 to 3 weeks. Inspections are required at the rough-in stage (before drywall goes up) and at final completion.

Check Your Municipality

Permit requirements, fees, and exemptions vary by municipality. Verify the specifics for your location.