Spot the Violation

PlumbingMinnesota plumbing licensing, permits & inspectionsLevel 12018 UPC

New bathroom for the lower unit

Front of a two-story up-and-down duplex in winter. Two entry doors are marked Upper and Lower. The upper-floor windows have curtains and a plant. A For Rent sign hangs in a lower-floor window, and a homeowner plumbing permit card is taped inside the glass of the Lower door. On the stoop by the Lower door sit an old toilet, coils of red and blue PEX, and lengths of white PVC pipe. FOR RENT 2 BR LOWER UNIT UPPER PLUMBING PERMIT HOMEOWNER LOWER
Up-and-down duplex, Saturday morning

The owner lives in the upper unit. The city issued him a homeowner plumbing permit, and he is replumbing the lower unit's bathroom himself before the next tenant moves in. What's the problem?

  1. The homeowner exemption covers only the part of the building the owner actually occupies, so the rental unit's plumbing must be done by a licensed plumbing contractor
  2. Owning the whole building is enough; the exemption covers every unit on the owner's property
  3. PEX is not allowed in a two-family dwelling, so the lower unit must be piped in copper
  4. Nothing. This installation is compliant
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Show the answer and the code reference

The answer

The owner is using the homeowner exemption to plumb a rental unit he does not live in, and the exemption covers only the part of the premises he owns and actually occupies.

Correct choice: 1. The homeowner exemption covers only the part of the building the owner actually occupies, so the rental unit's plumbing must be done by a licensed plumbing contractor

Minn. Stat. 326B.46 lets a person who is not licensed do plumbing that meets the Plumbing Board's standards only on premises, or that part of premises, owned and actually occupied by that person as a residence, and only where no local ordinance forbids it. In an up-and-down duplex, 'that part of premises' means the owner's own unit. Metro city permit handouts put it plainly: an unlicensed owner may not do plumbing on property rented, leased, or occupied by others. The rule protects tenants, who never chose an unlicensed installer for the drains and water lines they depend on. The lower unit's bathroom has to be done by a licensed plumbing contractor under its own permit.

How to fix it

Stop work in the lower unit and hire a licensed plumbing contractor to pull a permit and complete the bathroom. Any piping already installed must be inspected and tested, and redone if needed, under the contractor's permit. The owner may still do his own plumbing in the upper unit he lives in.

Code references

  • Minn. Stat. 326B.46, subd. 1 — License required; owner-occupant exemption

    Anyone not licensed may do plumbing work that complies with the Plumbing Board's minimum standards on premises, or that part of premises, owned and actually occupied by the worker as a residence, unless otherwise forbidden by local ordinance. Otherwise, plumbing work requires licensed individuals and a licensed contractor.

    Drills citing 326B.46, subd. 1

  • Other City permit handouts, 'When am I required to hire a licensed contractor?' (for example Anoka and White Bear Lake) — Homeowner plumbing and rental property

    Owners may do their own plumbing only on property they own and occupy. It is illegal for an unlicensed owner to do plumbing work on property that is rented, leased, or occupied by others, and plumbing permits for non-owner-occupied units must be taken out by a licensed plumbing contractor.

    Drills citing City permit handouts, 'When am I required to hire a licensed contractor?' (for example Anoka and White Bear Lake)

  • Minn. Stat. 326B.43 — Plumbing standards

    The Plumbing Board's minimum standards are uniform and apply to all new plumbing installations anywhere in the state, including additions, extensions, alterations, and replacements.

    Drills citing 326B.43

Minnesota

Minnesota ruleConfidence: medium

This drill tests Minnesota plumbing licensing law, which has no Uniform Plumbing Code counterpart. The owner exemption in Minn. Stat. 326B.46 covers only premises, or the part of premises, that the owner actually occupies, and a city ordinance may narrow it further. The plumbing itself must still meet the Minnesota Plumbing Code (Minn. Rules ch. 4714, the 2018 UPC with Minnesota amendments).

About the Minnesota Plumbing Code

Citation under review. Audited 2026-10-04. The exemption's 'that part of premises owned and actually occupied by the worker as a residence' wording and its place in subd. 1(a) were confirmed through search results quoting revisor.mn.gov (direct fetch blocked); subd. 1a(a) also lets that person work without a contractor license. The rental-property exclusion is not in those words in the statute. It comes from metro city permit handouts (Anoka, White Bear Lake, Inver Grove Heights 'When am I required to hire a licensed contractor' sheets) seen only in search summaries. No DLI page stating it was read, so the reference is attributed to the cities, not DLI.

Why the other choices are wrong

  • Owning the whole building is enough; the exemption covers every unit on the owner's property. Minn. Stat. 326B.46 exempts plumbing only on premises, or the part of premises, the person owns and actually occupies as a residence. The owner lives upstairs, not in the lower unit.
  • PEX is not allowed in a two-family dwelling, so the lower unit must be piped in copper. Listed PEX is an approved water distribution material under the plumbing code in one- and two-family dwellings. The pipe material isn't the issue; who is doing the work is.
  • Nothing. This installation is compliant. The lower unit is a rental the owner does not occupy, so the homeowner exemption and a homeowner permit cannot cover plumbing work there.
Code complianceLevel 1 · Apprentice#minnesota#licensing#homeowner-exemption#rental#duplex#permit

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