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Consumer information


Protect your health and property when having plumbing work done

Hiring a licensed, bonded and insured plumber can help to protect homeowners from non-complying work, costly errors, accidents, physical injury and improper plumbing installations. These potential problems can result in property damage and adverse health effects to building occupants.

  • State licensing - All plumbers statewide must be licensed or registered as an apprentice. A Minnesota plumbing license demonstrates that the plumber has years of practical, hands-on training, and a proven knowledge of plumbing codes, materials and approved construction methods. All plumbers' licenses must be renewed annually and should be carried at all times on a work site. Verify a license, bond or certificate issued by DLI here.

    The restricted plumbing licenses allow the holder to do work in the plumbing trade in all areas of the state except in cities and towns with a population of more than 5,000 according to the federal census. While a restricted plumbing license is only required by state law for cities with a population of less than 5,000, a smaller community may have a local statute that requires an unrestricted license. Always ask to see a master plumber license before signing any contracts for work in cities over 5,000.

    Restricted plumbers can be very competent; however, they have not had to demonstrate their professional competency through apprenticeship or through the journeyman or master licensing exams. Verify that the people actually doing the work are licensed as plumbers, or are registered plumber's apprentices working with continuous, on-site supervision by a licensed plumber.

  • Bonding requirement - Anyone contracting to do plumbing work must provide evidence of a $25,000 code compliance bond. The bond must be filed with the Department of Labor and Industry, must be renewed annually, and would be in effect for all work done by that contractor during that year.

    A bond helps protect the consumer from work that does not comply with the plumbing code. The state can use the bond amount to have non-complying work corrected.

  • Insurance coverage - Master plumbers who carry public liability insurance must have minimum limits of $50,000 per person and $100,000 per occurrence, and property damage insurance with minimum limits of $10,000.

Code compliance

All plumbing work statewide must comply with the state plumbing code. Adoption of the plumbing code through ordinance by a local form of government will allow the adopting form of government to enforce the code requirements.

What training and education does a licensed, Minnesota plumber have?

  • Plumber's apprentice - The apprentice position is the starting position for aspiring plumbers. Apprentices may register with the state of Minnesota and work under the direct on-site supervision of a licensed journeyman or master plumber. After four years and at least 7,000 hours of practical work experience, an apprentice becomes eligible to take an exam for a journeyman license.
  • Certified pipelayer - A certified pipelayer is an individual who has completed pipe-laying training in a program approved by the commissioner of the Department of Labor and Industry, and has a certificate to show record of the training. This certificate, or pipelayer's card, may be carried by an individual in lieu of a plumber license to work on water service pipes, building drain/sanitary sewer pipes and storm sewer pipes within the property lines of a facility or residence, but not inside buildings. This does not qualify a person to work on interior plumbing.
  • Restricted Journeyman Plumber - A restricted journeyman plumber was required to document at least two years of practical plumbing experience prior to Oct. 1, 2008. A restricted journeyman plumber must work under the direction of a master plumber or a restricted master plumber. A restricted journeyman may work without on-site supervision only in cities with a population of less then 5,000.
  • Restricted Master Plumber - A restricted master plumber was required to document at least four years of practical plumbing experience prior to Oct. 1, 2008. A restricted master plumber can bid on plumbing jobs, big and small, and may also design the plumbing systems that will be installed only in cities with a population of less then 5,000.
  • Journeyman Plumber - Apprentices who pass the exam can become licensed journeyman plumbers. Journeyman plumbers must work under the direction of a master plumber in any city with a population over 5,000. A licensed journeyman is considered knowledgeable and may work without on-site supervision.
  • Master Plumber - A licensed master plumber will have five or more years of practical work experience and knowledge of the Minnesota state plumbing code. He or she will have thousands of hours experience in water distribution systems, drain, waste and vent system installation, and fixture installation. A master plumber can bid on plumbing jobs, big and small, and may also design the plumbing systems that will be installed.

Who administers the plumbing program?

The Plumbing Board is responsible for adopting the Minnesota Plumbing Code and any amendments.

The commissioner of the Department of Labor and Industry is responsible for administering the statewide plumbing code and licensing requirements, and also for taking punitive actions against plumbers who fail to meet licensing or installation requirements. This responsibility is carried out in the Plumbing Plan Review and Inspection unit with the Department of Labor and Industry. If you have questions about plumbing codes, licensing requirements, or non-complying work, contact the Plumbing Plan Review and Inspection unit at (651) 284-5067 or dli.plumbing@state.mn.us.

  • Administrative or Punitive Measures - The state may take action against a plumber who does non-complying work. Possible actions against plumbers include invocation of the bond to correct non-complying work and/or administrative penalties through the Minn. Statutes, Section 144.989 to 144.993 which may result in monetary fines as well as licensure suspension or revocation penalties.
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