In Minneapolis, you can convert a single-family home or duplex to a three-unit dwelling. This type of conversion is a major project under the Minnesota Building Code.
Examples of a three-unit dwelling:
- Three-plex or four-plex
- Duplex with an accessory dwelling unit (ADU)
Converting a single-family home or duplex to a structure with 3 or more dwelling units is a significant undertaking under the Minnesota Building Code. The applicable building code section changes from 1309, Minnesota Residential Code (IRC) to 1305, Minnesota Building Code (IBC). This change in applicable code sections constitutes a special condition. Because of this, Construction Documents prepared by a Minnesota licensed architect are required for all projects converting a single family dwelling or duplex to a 3 or more unit apartment building.
Property owners who want to convert a single-family dwelling or duplex to a three or more unit building must:
- Learn relevant State and City rules.
- Hire an architect to prepare drawings showing how the building will comply with the building code.
- Complete a building permit application.
- Get zoning and plan review approval.
Step 1: Learn relevant State and City rules
When you convert a single-family home or duplex to a three or more unit building, the applicable building code changes:
- From the International Residential Code (IRC) requirements
- To R2 Occupancy (apartment) rules under the International Building Code (IBC)
If your converted dwelling will include a detached ADU, you will need to know the requirements for a detached ADU.
Step 2: Hire an architect to prepare a drawing
The architect will:
- Need to review the existing building
- Talk with the property owner about the issues to address to make this conversion
- Prepare a building code analysis and drawings showing the proposed changes needed to meet code requirements
Step 3: Complete a building permit application
After you have finished your floor plan, the next step is to complete a building permit application.
Completed building permit applications must be submitted by email. You will receive instructions to submit floor plans through the city's ProjectDox electronic plan system.
After you submit the building permit:
- You will receive an email from "ProjectDox@minneapolismn.gov."
- The email will explain the process to submit your floor plans using the City’s ProjectDox electronic plan system.
- After you submit the floor plans, City staff will do a zoning and plan review.
Step 4: Get zoning and plan review approval
When a property owner wants to change the use of a building, the City must do a zoning and plan review to approve the floor plan.
Staff people from two divisions in the City’s Community Planning & Economic Development (CPED) department will review your plan:
- CPED Zoning will verify that converting from a single-family dwelling to a duplex complies with the City Zoning Ordinance.
- CPED Construction Code Services will review for state building code requirements.
During the review, CPED might send you comments for correction. If this happens, you will need to correct the plans and resubmit them.
Once CPED approves your plans
- You will be notified by our electronic system to pay for the permit.
- Once you pay the fees, you will receive another notice from our electronic system . The notice will explain how to download your approved plans and building permit.
After you finish the building project
After you finish the project, the City will perform a certificate of occupancy inspection. Once CPED approves your work, we will:
- Issue a certificate of occupancy for the new building use that includes the number of units.
- Change the unit count record in department permit records.
- Notify the City’s Solid Waste & Recycling and Utility Billing (water department) that the conversion is complete. City services will then be billed according to the number of dwelling units.