Do I Need a Permit to Add a Bathroom in Wisconsin?
Adding a bathroom requires building, plumbing, and electrical permits in Wisconsin. This is one of the most permit-intensive home improvements.
Yes, you typically need a permit. Requirements vary by municipality. Check with your local building department for specifics.
Where to Apply
Permit requirements, fees, and processing times vary by municipality. Check the specific requirements for your location:
Browse all jurisdictions →Frequently Asked Questions
What permits do I need to add a bathroom?
Building permit (for framing and structural work), plumbing permit (for supply, drain, vent lines), and electrical permit (for circuits, GFCI outlets, and fan). All three are required.
Can I add a bathroom in my basement?
Yes, but you may need a sewage ejector pump if the basement drain is below the sewer line. This adds complexity and cost to the plumbing work.
How much does it cost to add a bathroom?
A full bathroom addition in Wisconsin typically costs $15,000-$50,000 depending on whether you are converting existing space or building an addition. Permits run $200-$600 total.
Building in multiple cities?
See permit requirements for any Wisconsin municipality instantly. Compare fees, timelines, and processes side by side across your active jurisdictions.