Missoula Duplex Conversion: Permit, Contracting, and Apprentice Supervision
A journeyman plumber employed by a licensed Montana plumbing contractor is assigned to a duplex in Missoula. The owner wants to replace two 50-gallon tank-type water heaters with condensing tankless units, add a hot-water recirculation loop, and convert an attached garage into a studio apartment with a new bathroom containing a water closet, lavatory, and shower. The contractor's master plumber is out of state for three weeks. The journeyman has one registered apprentice and is also asked by the owner to pull the permit under the journeyman license so the owner can save the contractor's permit fee. The city has adopted the 2021 UPC with local amendments and requires inspection before concealment. The apprentice is eager to run the new gas and water lines at the duplex while the journeyman finishes another job across town.
1. Identify the licensing and permitting problems in this request. Who may contract for the work and who may obtain the permit? Can the journeyman legally pull the permit under the journeyman license?
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The journeyman license authorizes work under a licensed plumbing contractor and master plumber; it is not a contracting license. A journeyman cannot contract directly with the owner, hold themselves out as the plumbing contractor, or obtain a plumbing permit as the contractor of record. Permits are normally issued to the licensed plumbing contractor or master plumber who is responsible for the work, subject to the local building department's rules. A limited owner-occupant exemption may exist in Montana for a person working on their own single-family residence, but a duplex with a rental unit and a garage conversion is not a safe reliance on that exemption. The correct path is for the licensed contractor to keep the permit in the contractor's name and have an available master plumber or qualifying party responsible for the project while the regular master is away. The journeyman can supervise and perform plumbing work within scope, but should not sign as contractor or accept the owner's request to use the journeyman license as a permit vehicle. Confirm the exact permit-signature rule with the Missoula AHJ and the Montana Board before work starts.
2. What supervision is required for the apprentice, and can the apprentice work alone at the duplex while the journeyman is across town?
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An apprentice must work under the supervision of a licensed journeyman or master plumber as required by Montana statutes and Board rules. The key judgment is that supervision must be real and on-site, not a phone call from another job. Leaving the apprentice alone to run gas piping and water lines at the duplex would be unsupervised plumbing work and would also create a permit and inspection problem. The journeyman should either remain on-site while the apprentice performs the work or arrange for another licensed journeyman or master to provide direct supervision. The journeyman should also check the applicable apprentice-to-journeyman ratio in the Board rules before assigning the apprentice, because the ratio and supervision standards are administrative requirements separate from the technical code. If the contractor cannot staff the duplex with proper supervision, the work should be scheduled for a time when the master returns or another qualified supervisor is present.
3. List the inspection and sequencing steps that should occur before the garage bathroom and water heater work are concealed or put into service.
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Before concealment, the rough-in drainage and water piping should be inspected and tested as required by the adopted code and local amendments. That means the new bathroom drain, vent, and water lines must be complete, supported, and tested before drywall or concrete closes them. Gas piping should be pressure-tested and inspected before the tankless units are fired. The water heater installation should be checked for clearances, venting, combustion air, relief valve discharge, and thermal expansion control where the system is closed. The contractor should request the rough-in inspection with the approved plans and permit on site, correct any failed items, and only then cover the work. A final inspection should follow after fixtures, water heaters, and recirculation controls are installed and the system has been tested for leaks and proper operation. Because the city requires inspection before concealment, backfilling or drywalling early would be a sequencing violation even if the installation itself were later found acceptable.