Minnesota plumbing code: which edition applies and what it requires

Does Minnesota use the IPC or the UPC?

Minnesota uses the UPC as its base, but with extensive Minnesota amendments. The Minnesota Plumbing Code is built on the Uniform Plumbing Code.

Minnesota's amendments are significant for trap seals specifically (see below), so the base UPC text cannot be assumed to apply unchanged.

What edition of the plumbing code does Minnesota use, and when did it take effect?

Minnesota's current edition is 2020 MN Plumbing Code (2018 UPC base), effective 2021-12-17, adopted by the MN Dept of Labor and Industry (DLI) / MN Plumbing Board.

Codes update on a multi-year cycle, and an adopted-but-not-yet-effective edition can circulate near a changeover. Confirm which edition your project falls under by its permit date and your local jurisdiction.

How do local jurisdictions affect Minnesota's plumbing code?

Minnesota's code is the statewide baseline, but local jurisdictions enforce it and may add amendments. The local authority having jurisdiction (AHJ) resolves how it applies to a specific project.

Statewide; extensive MN part-by-part amendments to the UPC. Confirm any local amendments and the accepted trap-seal methods with your city or county building department before relying on a provision.

What does the plumbing code require for floor drains and trap seals?

Floor drains rely on a trap, and the code requires that trap seal to be maintained. A floor drain that receives little water can lose its seal to evaporation, which opens a path for sewer gas, odors, and pests.

To prevent that, codes recognize trap seal protection methods. The two most common are a trap seal primer (which adds water to the trap) and a barrier-type floor drain trap seal protection device (which provides a mechanical seal). The right approach depends on the drain, the space, and the AHJ.

Minnesota adopts the UPC but deletes Section 1007 (trap seal protection) in full, so its code carries no barrier-type / ASSE 1072 provision; a barrier device is handled as an AHJ alternative method.

Are barrier-type (ASSE 1072) trap seals allowed under Minnesota's code?

Not by name. Minnesota deletes UPC Section 1007 (trap seal protection) in its entirety, so the code does not carry the ASSE 1072 provision.

That does not prohibit a barrier-type device; it means acceptance is an alternative-materials-and-methods decision made by the local AHJ. Present the device's cUPC and ASSE 1072 listing to the AHJ, and lean on the evaporation / preventive-maintenance rationale. Do not rely on a code-compliance claim here.

Do I need a permit to add a floor-drain trap seal in Minnesota?

Usually not for the device itself, but always confirm with your local authority having jurisdiction.

A drop-in barrier-type trap seal device generally does not require a plumbing permit because it does not alter any piping, similar to changing a drain grate. On new construction or an already-permitted renovation, include it in the plumbing specifications.

In Minnesota, plumbing permits and inspections run through MN Dept of Labor and Industry and the local building department, and a licensed plumber pulls permits for plumbing work. Licensing rules and reciprocity vary, so confirm them with the authority or your local jurisdiction.

Where can I read Minnesota's plumbing code?

The adopting authority and code text are linked below. Always confirm current requirements against the adopted code and your local AHJ.

• www.dli.mn.gov/business/plumbing-contractors/202...
• www.revisor.mn.gov/rules/4714/full
• www.revisor.mn.gov/rules/4714.1006/