IA Plumber study guide
IA Plumber · Work through your exam, one topic at a time.
An Iowa plumber license is a state-issued credential that authorizes a person to install, alter, and repair plumbing systems under Iowa's plumbing law and the plumbing code the state has adopted. It is administered at the state level through the Iowa Plumbing and Mechanical Systems Board, and it comes in tiers: journeyman, master, and plumbing contractor. The IA Plumber study guide has 10 sections and about 3,747 words.
01General Regulations: Permits, Inspections, and the AHJ
General regulations chapters set the framework rather than the pipe sizes: who may do the work, when a permit is required, what must be inspected before it is covered, and how the authority having jurisdiction (AHJ) - usually the plumbing official - applies and interprets the code. The code is a minimum standard; nothing in it prohibits better workmanship or more generous sizing.
339 words, about 2 min02Plumbing Math and Pipe Sizing Calculations
Most missed items in this domain are vocabulary failures. If you cannot distinguish a soil stack from a vent stack, or a building drain from a building sewer, the sizing and venting questions become unanswerable.
695 words, about 3 min03Drainage Systems and Drainage Piping
Drainage is gravity-driven and self-scouring. Every requirement - slope, fitting type, venting, cleanouts - exists to move solids, protect trap seals, and keep the pipe clear.
354 words, about 2 min04Vents and Venting Systems
A vent does two jobs: it lets air into the drainage system so flow doesn't siphon trap seals, and it lets sewer gas escape above the roof. Every trap must be vented, and the vent must connect so that it cannot become a drain.
382 words, about 2 min05Traps, Interceptors and Special Wastes
The trap holds a water seal - commonly 2 to 4 inches - that blocks sewer gas. Everything in this domain protects that seal or protects the sewer from what the fixture discharges.
325 words, about 2 min06Water Supply and Water Distribution
Trace the system: water main → service line → meter → building distribution → risers → fixture supply. Design is governed by pressure , not pipe size alone.
329 words, about 2 min07Plumbing Fixtures and Fixture Fittings
Fixture questions test whether you know the installation requirements - spacing, clearance, support, sealing, backflow protection, and accessibility - not just the fixture's name. Water closets are conventionally set with the centerline at least 15 inches from a side wall or partition and at least 15 inches from the centerline of an adjacent fixture, in a compartment at least 30 inches wide .
319 words, about 2 min08Water Heaters and Temperature Control
The temperature and pressure (T&P) relief valve is the single most tested item. It must be the correct rating for the tank, installed in the designated opening (commonly within the top 6 in of the tank), and never plugged, capped, or valved.
337 words, about 2 min09Fuel Gas Piping and Gas Appliances
Gas piping is sized by the longest-length method : measure from the meter to the farthest appliance (developed length, including fittings), total the connected load in Btu/h, then read the table for the available pressure and allowable drop. Tables assume a gas specific gravity near 0.60 and a defined pressure drop - using a different gas or pressure invalidates the table.
348 words, about 2 min10Backflow Prevention and Cross-Connection Control
A cross-connection is any actual or potential link between potable and nonpotable water. Backsiphonage is caused by negative pressure in the supply; backpressure is caused by downstream pressure exceeding supply pressure.
319 words, about 2 min