Do You Need a Permit to Finish a Basement in Bismarck or Mandan?

Who this is for: homeowners planning a basement finish in Bismarck or Mandan, and buyers or real estate agents checking whether a finished basement was done right.

The short answer

Yes. In Bismarck, "Basement Finish" is on the city's list of projects that require a permit, and electrical, plumbing and HVAC work each need their own permit as well (checked October 2026). In Mandan, permits go through the city's Permitting service; call the Building Department at (701) 667-3230 before you plan the work. Outside city limits, the permitting office depends on the address.

For a basement finish with HHI, tell us the property address. We identify the permitting office, discuss the required inspections, and state who will file and who pays the fees in your written scope. This guide is a plain-language summary of the city's published rules, not legal advice. Codes change, so verify with the city before you build.

What needs a permit in Bismarck

The City of Bismarck lists these project types as requiring a permit:

• Additions, renovations and remodels, including basement finishes, decks, sheds, garages, pools, sunrooms and gazebos
• Electrical wiring
• Plumbing
• HVAC, including furnaces, water heaters, boilers, air conditioners, unit heaters and fireplaces

So a typical basement finish needs a building permit plus separate trade permits for new circuits, a bathroom, or extended heating. If you're not sure whether a smaller project counts, the city asks you to call the Building Inspections Division at (701) 355-1465.

Egress windows: the rules that shape your layout

Egress windows are the requirement most likely to change a basement plan. Under the city's building inspections FAQ, a finished basement needs an egress window in each bedroom, and a finished basement with no bedrooms still needs at least one. Here's what the City of Bismarck Building Inspections FAQ says, as checked in October 2026:

Bismarck egress window requirements for basements (city FAQ, checked October 2026)

Requirement	What the city says
Where you need one	Each basement bedroom; at least one in a finished basement even with no bedrooms
Net clear opening	At least 5.7 sq ft (main-floor sleeping rooms can be 5 sq ft)
Sill height	No more than 44 inches above the floor
Window well size	At least 9 sq ft of horizontal area, with a projection and width of at least 36 inches
Window well clearance	The well must let the window open fully
Ladder or steps	Required, permanently attached, if the well is deeper than 44 inches, and usable with the window fully open

"Net clear opening" means the actual open space a person can climb through with the window fully open, not the size of the frame. That's why an existing small basement window rarely qualifies, and why adding a bedroom often means cutting a larger opening in the foundation and installing a new window well. If you're budgeting, egress windows are one of the main reasons basement prices vary. Our guide to what finishing a basement costs here breaks that down.

Egress minimums at a glance: a net clear opening of at least 5.7 sq ft that is at least 24 inches high and 20 inches wide (2021 IRC, Section R310), a sill no more than 44 inches above the floor, and a window well of at least 9 sq ft with a ladder or steps once it's deeper than 44 inches. Which window styles pass, the ladder alternatives Bismarck allows, well covers, how Mandan's state code differs and digging in winter are all covered in our guide to egress window sizes, window wells and permits in Bismarck-Mandan.

Stairs and other details inspectors look at

The stairs are the other place basement finishes commonly need work. The city's FAQ lists these requirements:

• Headroom: at least 6 feet 8 inches (80 inches) of clearance over the stairs
• Risers and treads: risers no taller than 8 inches and treads at least 9 inches deep, with no more than 3/8 inch of difference between steps
• Handrail: continuous, between 34 and 38 inches high
• Under-stair storage: if the space under the stairs is enclosed and accessible, its walls, underside and soffits must be covered on the enclosed side with 1/2-inch gypsum board

The city also requires heating that can keep every habitable room at 68 degrees or more, so plan the heat source for a new bedroom or family room early. Low ductwork or a beam over the stairs can eat into headroom, and that's much easier to solve before framing starts.

Inspections

According to the city's FAQ, no inspection is required before you tape and texture the drywall, and a final inspection is required once the whole project is finished. Electrical, plumbing and HVAC permits come with their own inspections, which happen while the work is still visible. Three details worth getting right before an inspection: fireblocking, egress window size, and smoke and carbon monoxide alarm placement.

How long the permit takes, and how to apply

Usually about a day. The city says most permits other than new construction can be issued within 1 business day, compared with 7 to 10 business days for residential new construction.

To apply in Bismarck:

• Use the city's Basement Finish Application (last revised April 8, 2021). It asks for the contractor and contractor number, a contact person, the property address, the total square feet being finished and the rooms being finished.
• Submit online through eTRAKiT, which the city says is open to registered contractors and public users, or by email to [email protected].
• Questions go to the Building Inspections Division at (701) 355-1465. The office is at 221 N. 5th St.

If you plan to do the work yourself, ask the Building Inspections Division how they handle a homeowner application before you start, since the form is set up around a contractor. We don't list permit fees here because they change; the city can quote the current fee for your scope.

Mandan: who to call and what to ask

Mandan's Building Inspection department issues building permits and inspects the work, but its basement requirements aren't spelled out online the way Bismarck's are. Call (701) 667-3230 before you finalize a plan. The office is in City Hall at 205 Second Avenue NW and is open Monday through Thursday 8 a.m. to 5 p.m. and Friday 8 a.m. to 4:30 p.m.

Questions worth asking:

• Does my basement finish need a building permit, and which trade permits?
• Which egress window, stair and headroom rules apply?
• Which inspections are required, and at what stage?
• Can I apply as a homeowner, or does a licensed contractor need to apply?

If you're planning remodeling in Mandan, we can handle that call as part of the estimate.

What happens if you skip the permit

The City of Bismarck puts it plainly: projects not done according to code can affect your home's insurability and its potential sale, and buyers can check the city's building records. An unpermitted bedroom without a proper egress window is a safety problem first and a resale problem second, and fixing it later costs more than doing it right the first time.

Codes change: what Bismarck uses today

Bismarck currently uses the 2021 International Residential Code and related 2021 I-codes. Plumbing follows the Uniform Plumbing Code with North Dakota's state plumbing standards, and electrical follows the National Electrical Code with the state wiring standards (City of Bismarck, Building Codes). The city is in the process of updating to the 2024 editions, with draft amendments published for review. The rules in this article reflect what the city published as of October 2026. Before you build, confirm the current requirements with the city.

Before you apply

A permit covers the build, but it won't tell you whether the basement is ready to finish. Before you lock in a layout, check the space for water history, cracks, humidity and radon. Our guide to moisture and radon checks walks through each one.

Frequently asked questions

Do I need a permit to build walls in my basement?

In Bismarck, if the walls are part of turning the basement into finished space, that's a basement finish, and it's on the city's permit-required list. Any new wiring, plumbing or heating in those walls needs its own trade permit too. For a smaller project you're unsure about, call Building Inspections at (701) 355-1465 before you start.

What happens if I don't pull a permit to finish my basement?

Bismarck says work not done to code can affect your home's insurability and potential sale, and buyers can look up building records. You may also end up opening finished walls for inspection or adding an egress window after the fact. A permit usually takes about a business day, so skipping it saves very little.

How long does it take to get a building permit in Bismarck?

For a basement finish, usually about a day. The City of Bismarck says most permits other than new construction can be issued within 1 business day. Residential new construction takes longer, 7 to 10 business days. Mandan doesn't publish review times online, so call Building Inspection at (701) 667-3230.

Do I need an egress window if there's no bedroom in the basement?

In Bismarck, yes. The city's FAQ says a finished basement needs an egress window in each bedroom, and a finished basement with no bedrooms still needs at least one. It must have at least 5.7 square feet of net clear opening and a sill no higher than 44 inches above the floor.

Want help with the permit? We'll walk the basement, flag egress, stair and moisture issues, and give you a free written estimate that shows the permit and inspection steps and who files. Call or text Viktor at (701) 329-9659 with your town, photos and what you want to change. Our office follows up during business hours. HHI is licensed in North Dakota (contractor license No. 000050538, Class D), and our employees are covered through WSI.