MI Plumber study guide
MI Plumber · Work through your exam, one topic at a time.
A Michigan plumber license is a state-issued credential that authorizes a person to perform plumbing work for compensation in Michigan. The licensing program is administered by the Michigan Department of Licensing and Regulatory Affairs (LARA), and the examinations are the assessment step that separates an apprentice or a candidate with qualifying experience from a licensed journeyman or master plumber. The MI Plumber study guide has 10 sections and about 3,309 words.
01General Regulations, Definitions, and Administration
Michigan enforces the International Plumbing Code as amended by the state, adopted through local enforcing agencies that issue permits and perform inspections. Know the admin basics: a permit is required before a plumbing system is installed, altered, replaced, or extended; work must be performed by a licensed plumber (with limited owner-occupant exceptions where local ordinance allows); and inspections are required at rough-in - before piping is covered - and at final.
300 words, about 2 min02Drainage Systems
Gravity drainage depends on slope. Horizontal drainage pipe 2½ inches and smaller slopes at ¼ inch per foot; 3 inches and larger at ⅛ inch per foot.
320 words, about 2 min03Vents and Venting
A vent equalizes pressure so trap seals are not siphoned. Every trap must be protected by a vent sized and installed per the tables.
346 words, about 2 min04Water Supply and Distribution
Distribution is sized by water supply fixture units (wsfu) and developed length. Know the pressure rules: the code sets a minimum residual pressure at fixtures (roughly 8 psi flowing) and requires a pressure-reducing valve when static pressure exceeds 80 psi .
316 words, about 2 min05Fixtures, Fixture Fittings, and Appliances
Drainage fixture units drive sizing. Common private-residential values: water closet 3 dfu, lavatory 1, bathtub or shower 2, kitchen sink 2, floor drain 2, clothes washer standpipe 2, dishwasher 2.
316 words, about 2 min06Traps, Interceptors, and Special Wastes
The trap seal must be at least 2 inches and no more than 4 inches deep. Traps must be set level so the seal is not spilled, must be self-cleaning, and must be accessible for cleaning.
348 words, about 2 min07Storm Drainage
Storm drainage from roofs, courtyards, and subsoil drains must be kept out of the sanitary sewer unless the building is served by a combined sewer approved by the authority. Roof leaders, conductors, area drains, and footing drains are part of the storm system and are sized separately from sanitary drainage.
366 words, about 2 min08Plumbing Math, Sizing, and Isometric Analysis
A plumbing isometric shows three axes 120 degrees apart: vertical risers, and two horizontals. Trace the system from the building drain upward, labeling every stack, branch, and vent.
305 words, about 2 min09Safety, Tools, and Installation Practices
Drainage and vent systems are tested before covering. The standard water test fills the system to a 10-foot head above the highest point and holds for 15 minutes with no drop; air tests are permitted only where approved and at the pressure the code specifies.
324 words, about 2 min10Fuel Gas Piping and Gas-Fired Appliances
Michigan adopts the International Fuel Gas Code (NFPA 54). Gas piping is sized by the longest-length method using the total connected load in Btu/h, the gas's specific gravity and heating value, and the allowable pressure drop.
368 words, about 2 min