ICC Journeyman Plumber - G25-N Exam Prep Guide

The ICC Journeyman Plumber - G25-N examination is designed for plumbing professionals preparing to demonstrate their knowledge of plumbing regulations, fixtures, water heaters, water supply systems, sanitary drainage, venting, traps, interceptors, storm drainage, plan reading, and code-compliant installation practices.

The ICC Journeyman Plumber - G25-N exam prep collection includes a books and courses rental package, professionally highlighted and tabbed books, flexible online exam preparation, and a standard exam book package.

This guide explains the available G25-N preparation options, major plumbing study areas, calculation topics, code-navigation methods, and practical strategies for preparing for a journeyman-level plumbing examination.

Available G25-N Exam Prep Packages

• ICC Journeyman Plumber - G25-N - Books & Courses Rental Package: $540.00 sale price, reduced from $840.00
• ICC Journeyman Plumber - G25-N Highlighted & Tabbed Book Package: $245.00 sale price, reduced from $445.00
• ICC Journeyman Plumber - G25-N - Online Exam Prep: $295.00 sale price, reduced from $395.00
• ICC Journeyman Plumber - G25-N Exam Book Package: $129.00 sale price, reduced from $229.00

The rental package combines temporary access to the exam reference with online training. The highlighted and tabbed package supports faster code navigation. The online course is suitable for candidates who already own the correct book, while the exam book package supports independent study.

Books & Courses Rental Package

The ICC Journeyman Plumber - G25-N Books & Courses Rental Package combines temporary access to the assigned plumbing reference with structured online exam preparation.

The package is listed at a sale price of $540.00, reduced from the regular price of $840.00.

This package may be appropriate for candidates who:

• Need the exam book and online course together
• Do not currently own the approved plumbing reference
• Want an organized journeyman plumber study plan
• Need help navigating plumbing code chapters and tables
• Want practice with drainage, venting, and water-supply questions
• Prefer combining lessons, book study, and practice exams

Candidates should review the current product listing for the rental period, refundable deposit, course-access period, shipping details, and return instructions.

Highlighted & Tabbed Book Package

The ICC Journeyman Plumber - G25-N Highlighted & Tabbed Book Package provides a professionally organized plumbing code reference for candidates who want to begin studying without marking every section themselves.

The package is listed at a sale price of $245.00, reduced from the regular price of $445.00.

The prepared book may help candidates locate:

• Code definitions and general regulations
• Plumbing fixture requirements
• Water heater provisions
• Water supply and distribution tables
• Sanitary drainage requirements
• Vent sizing and installation rules
• Trap, interceptor, and separator provisions
• Storm drainage requirements

Highlighted and tabbed books can improve navigation, but candidates must still understand how to interpret tables, exceptions, definitions, and installation requirements.

Online Exam Prep

The ICC Journeyman Plumber - G25-N Online Exam Prep course provides flexible, self-paced preparation for candidates who already own the correct reference or plan to purchase it separately.

The course is listed at a sale price of $295.00, reduced from the regular price of $395.00.

Online preparation may help candidates:

• Review plumbing subjects in a logical order
• Practice code-navigation techniques
• Work through drainage and venting questions
• Review water pipe and drainage pipe sizing
• Improve plan-reading skills
• Identify weak knowledge areas
• Complete exam-style practice questions
• Study around an active plumbing schedule

The course is most effective when candidates use the approved plumbing code while completing lessons and practice questions.

Exam Book Package

The ICC Journeyman Plumber - G25-N Exam Book Package provides the primary printed plumbing reference associated with the examination for independent study.

The package is listed at a sale price of $129.00, reduced from the regular price of $229.00.

This package may be appropriate for candidates who:

• Prefer independent book-based preparation
• Want to own the plumbing code reference
• Already understand many journeyman plumbing subjects
• Want to create a personalized tab and highlighting system
• Already have separate training or practice questions
• Need the book for continued professional use

What Is the ICC G25-N Examination?

The G25-N examination is associated with the ICC National Standard Journeyman Plumber Contractor and Trades examination path. Participating jurisdictions may use it as part of a journeyman plumber licensing, registration, or qualification process.

The examination is reference-based and may require candidates to locate and apply plumbing code provisions under timed conditions.

Questions may test a candidate’s ability to:

• Interpret plumbing code language
• Use fixture-unit and pipe-sizing tables
• Determine approved materials and installation methods
• Size water supply and distribution piping
• Size sanitary drainage piping
• Apply venting requirements
• Evaluate traps, interceptors, and separators
• Review water heater installations
• Interpret plumbing plans and diagrams
• Recognize unsafe or noncompliant installations

Exam question totals and time limits may vary among current product descriptions or testing programs. Candidates should confirm the current G25-N bulletin and the requirements of the licensing authority before registering.

G25-N Exam Reference

The current package information identifies the following primary reference:

• International Plumbing Code, 2018 Edition

The International Plumbing Code covers plumbing system design, materials, fixtures, water heaters, water supply and distribution, sanitary drainage, vents, traps, interceptors, separators, storm drainage, and related installation requirements.

Candidates should confirm that the 2018 edition matches their scheduled examination because jurisdictions and exam programs may adopt different code cycles.

Confirm Local Licensing Requirements

Passing G25-N does not automatically issue a journeyman plumber license in every jurisdiction.

Before purchasing materials or scheduling the examination, candidates should verify:

• Whether the licensing authority accepts G25-N
• The required International Plumbing Code edition
• The current approved reference list
• The number of examination questions
• The testing time
• The required passing score
• Whether the examination is open book
• Rules for tabs, highlighting, and handwritten notes
• Required plumbing work experience
• Apprenticeship or education requirements
• Application and examination fees
• License renewal and continuing-education requirements

What Does a Journeyman Plumber Do?

A journeyman plumber installs, alters, repairs, tests, and maintains plumbing systems within the scope allowed by the applicable licensing authority.

Common responsibilities may include:

• Reading plumbing plans and specifications
• Installing water service and distribution piping
• Installing sanitary drainage systems
• Installing vent piping
• Connecting plumbing fixtures
• Installing water heaters
• Installing traps, cleanouts, and interceptors
• Testing water and drainage systems
• Protecting potable water from contamination
• Correcting plumbing code deficiencies
• Coordinating permits and inspections
• Following jobsite safety requirements

The exact scope of permitted work depends on local licensing laws and supervision requirements.

Common G25-N Study Areas

• Code administration and general regulations
• Plumbing definitions
• Approved materials and joints
• Plumbing fixtures
• Fixture clearances and accessibility
• Water heaters
• Water supply and distribution
• Backflow prevention
• Sanitary drainage
• Cleanouts
• Venting systems
• Traps
• Interceptors and separators
• Storm drainage
• Plan reading
• Testing and inspections

Code Administration and General Regulations

Journeyman plumbers should understand how plumbing work moves through permitting, inspection, testing, and final approval.

Study subjects may include:

• Permit requirements
• Construction documents
• Required inspections
• Approved materials
• Alternative materials and methods
• Protection of piping
• Equipment access
• Testing requirements
• Unsafe conditions
• Code official authority
• Contractor and installer responsibilities

Plumbing Materials

Plumbing materials must be approved for the system, pressure, temperature, environment, and installation method.

Materials may include:

• Copper and copper-alloy pipe
• Cast-iron soil pipe
• Galvanized steel pipe
• Stainless steel pipe
• PVC pipe
• CPVC pipe
• ABS pipe
• PEX tubing
• Polyethylene piping
• Approved fittings and transition fittings

Candidates should identify the system and material before selecting a joining, support, testing, or protection requirement.

Pipe Joints and Connections

Joints must be compatible with the piping material and suitable for the operating conditions.

Possible joining methods may include:

• Soldered joints
• Brazed joints
• Threaded joints
• Welded joints
• Solvent-cemented joints
• Mechanical joints
• Pressed connections
• Compression fittings
• Flared connections
• Heat-fusion joints

Candidates should also review transition fittings used when different pipe materials are connected.

Pipe Support and Protection

Plumbing piping must be supported to prevent sagging, movement, joint stress, and damage.

Important subjects may include:

• Horizontal support spacing
• Vertical support
• Support near changes in direction
• Protection through framing members
• Protective plates
• Protection from freezing
• Protection from corrosion
• Underground bedding and backfill
• Expansion and contraction
• Protection from physical damage

Plumbing Fixtures

Plumbing fixture requirements address approved products, installation, clearances, water supply, drainage, and accessibility.

Common fixtures include:

• Water closets
• Urinals
• Lavatories
• Kitchen sinks
• Service sinks
• Bathtubs
• Showers
• Drinking fountains
• Dishwashing equipment
• Clothes-washing machines
• Floor drains
• Emergency fixtures

Candidates should review fixture-unit values, required clearances, trap requirements, waste connections, and water-supply connections.

Required Number of Fixtures

Some questions may require candidates to determine the minimum number of plumbing fixtures for a building or occupancy.

Important considerations may include:

• Occupancy classification
• Occupant load
• Number of males and females
• Water closets
• Urinals
• Lavatories
• Drinking fountains
• Service sinks
• Separate facilities
• Fixture substitutions and exceptions

Candidates should read table headings, footnotes, and exceptions carefully.

Fixture Clearances and Installation

Fixtures must be installed with sufficient space for use, cleaning, maintenance, and accessibility.

Study areas may include:

• Water closet clearances
• Urinal spacing
• Shower dimensions
• Bathtub installation
• Fixture support
• Wall-hung fixture carriers
• Access to concealed connections
• Sealing around fixtures
• Accessible fixture requirements
• Protection from damage

Water Heaters

Water heater questions may involve installation, capacity, temperature control, pressure protection, combustion air, venting, drainage, and accessibility.

Candidates should review:

• Water heater locations
• Required clearances
• Temperature and pressure relief valves
• Relief discharge piping
• Drain pans
• Expansion control
• Cold-water shutoff valves
• Thermal expansion tanks
• Combustion air
• Venting
• Garage installation
• Protection from physical damage

Temperature and Pressure Relief

Storage water heaters require approved protection against excessive temperature and pressure.

Study subjects may include:

• Relief valve location
• Valve rating
• Discharge pipe size
• Permitted discharge materials
• Termination location
• Air gaps
• Prohibited valves or restrictions
• Drainage to an approved location
• Protection from freezing

Water Supply and Distribution

Water distribution systems must provide potable water at suitable pressure and flow to every required fixture and appliance.

Study subjects may include:

• Water service piping
• Water distribution piping
• Pipe sizing
• Fixture-unit calculations
• Available water pressure
• Pressure loss
• Elevation changes
• Pressure-reducing valves
• Water hammer control
• Thermal expansion
• Hot-water distribution
• Circulation systems

Water Pipe-Sizing Calculations

Water pipe sizing may require candidates to use fixture units, developed length, available pressure, elevation, and pressure-loss information.

A practical process may include:

• Identify the fixtures served
• Determine the water-supply fixture units
• Calculate the developed pipe length
• Determine available supply pressure
• Account for elevation pressure loss
• Account for equipment and meter losses
• Select the applicable sizing table
• Choose a pipe size with adequate capacity

Candidates should identify whether the question concerns a building supply, water service, branch, riser, or individual fixture connection.

Water Pressure

Water pressure must be sufficient to operate fixtures while remaining below limits that could damage piping, valves, or equipment.

Study considerations may include:

• Minimum fixture pressure
• Maximum static pressure
• Pressure-reducing valves
• Elevation loss
• Friction loss
• Booster systems
• Pressure tanks
• Pressure fluctuations
• Water hammer
• Thermal expansion

Backflow Prevention

Backflow prevention protects potable water from contamination caused by backsiphonage or backpressure.

Candidates should review:

• Air gaps
• Atmospheric vacuum breakers
• Pressure vacuum breakers
• Reduced-pressure-principle assemblies
• Double-check assemblies
• Hose connection vacuum breakers
• Dual-check devices
• Required device locations
• Installation clearances
• Testing and accessibility

The degree of hazard and type of potential backflow determine the required protection.

Hot-Water Distribution

Hot-water systems must deliver water safely and efficiently while controlling temperature and pressure.

Study subjects may include:

• Hot-water pipe sizing
• Temperature limitations
• Tempering valves
• Recirculation systems
• Pipe insulation
• Dead-end lengths
• Thermal expansion
• Fixture temperature controls
• Scald protection
• Energy-conservation requirements

Sanitary Drainage Systems

Sanitary drainage systems carry wastewater from fixtures to the building sewer or another approved disposal point.

Important preparation subjects include:

• Drainage fixture units
• Horizontal drainage piping
• Vertical stacks
• Building drains
• Building sewers
• Drainage pipe sizing
• Required slope
• Changes in direction
• Cleanouts
• Prohibited connections
• Sumps and ejectors
• Testing

Drainage Fixture Units

Drainage fixture units represent the probable discharge load produced by plumbing fixtures.

Candidates may need to:

• Determine individual fixture-unit values
• Add fixture units on a branch
• Calculate stack loads
• Calculate building drain loads
• Select pipe sizes from drainage tables
• Apply limitations for specific fixtures
• Interpret table notes and exceptions

Drainage Pipe Sizing and Slope

Drainage pipe size and slope must support the expected discharge while maintaining flow and preventing blockages.

Study considerations may include:

• Drainage fixture-unit load
• Horizontal or vertical orientation
• Required pipe slope
• Building drain sizing
• Building sewer sizing
• Branch interval limits
• Stack sizing
• Fixture drain sizing
• Minimum pipe sizes

Candidates should select the correct table for the part of the drainage system described.

Changes in Drainage Direction

Drainage fittings must direct flow smoothly and reduce the possibility of blockage.

Study subjects may include:

• Horizontal-to-horizontal changes
• Vertical-to-horizontal changes
• Horizontal-to-vertical changes
• Approved drainage fittings
• Combination fittings
• Wyes
• Sanitary tees
• Quarter bends
• Long-turn fittings
• Base-of-stack fittings

Cleanouts

Cleanouts provide access for inspection, cleaning, and removal of drainage obstructions.

Candidates should review:

• Required cleanout locations
• Maximum spacing
• Changes in direction
• Building drain cleanouts
• Building sewer cleanouts
• Stack cleanouts
• Cleanout size
• Required clearance
• Access after construction
• Protection from damage

Sumps and Sewage Ejectors

Fixtures located below the level of the gravity building sewer may require a sump and pumping system.

Study subjects may include:

• Sump construction
• Gas-tight covers
• Pump capacity
• Discharge piping
• Check valves
• Shutoff valves
• Vent connections
• Alarm systems
• Access for service
• Emergency power where required

Plumbing Vent Systems

Vent systems protect trap seals and allow drainage systems to operate at atmospheric pressure.

Common venting methods may include:

• Individual vents
• Common vents
• Wet vents
• Circuit vents
• Combination waste and vent systems
• Stack vents
• Vent stacks
• Relief vents
• Island fixture vents
• Air admittance valves where permitted

Candidates should identify the venting method before applying sizing, connection, and installation requirements.

Vent Sizing

Vent size may depend on the drainage load, developed vent length, connected fixture units, and the drainage pipe served.

A practical process includes:

• Identify the drainage pipe or fixture being vented
• Determine the connected drainage fixture units
• Determine the developed vent length
• Select the applicable vent-sizing table
• Check minimum vent sizes
• Confirm termination and connection requirements

Trap Arms

A trap arm connects a fixture trap to the vented drainage system.

Study subjects may include:

• Trap-arm length
• Trap-arm slope
• Pipe size
• Distance to the vent
• Changes in direction
• Fixture connection
• Prohibited configurations
• Relationship between slope and trap-seal protection

Wet Venting

Wet venting allows a section of drainage piping to serve as both a drain and a vent when specific conditions are satisfied.

Candidates should review:

• Permitted fixture groups
• Bathroom-group arrangements
• Pipe sizing
• Fixture connection order
• Horizontal wet venting
• Vertical wet venting
• Vent connection requirements
• Prohibited fixtures or arrangements

Vent Termination

Plumbing vents must terminate where sewer gases will not enter the building or create an unsafe condition.

Study areas may include:

• Termination through the roof
• Clearance from windows and doors
• Clearance from air intakes
• Height above the roof
• Protection from frost closure
• Sidewall termination where permitted
• Combination of vent terminals
• Protection from physical damage

Traps

Fixture traps maintain a water seal that helps prevent sewer gases from entering occupied spaces.

Important study subjects include:

• Required trap locations
• Trap-seal depth
• Trap size
• Trap accessibility
• Prohibited traps
• Double trapping
• Trap primers
• Protection from evaporation
• Integral fixture traps
• Building traps where permitted

Interceptors and Separators

Interceptors and separators remove grease, oil, sand, sediment, lint, solids, or other materials before they enter the drainage system.

Common devices may include:

• Grease interceptors
• Grease traps
• Oil separators
• Sand interceptors
• Lint interceptors
• Hair interceptors
• Food-waste interceptors
• Special-purpose separators

Candidates should review required locations, sizing, access, ventilation, maintenance, and prohibited connections.

Grease Interceptors

Grease interceptors may be required for commercial food preparation and other operations that discharge fats, oils, or grease.

Study considerations may include:

• Required fixtures
• Interceptor type
• Flow rate
• Fixture capacity
• Location
• Access for cleaning
• Venting
• Flow-control devices
• Maintenance responsibility
• Prohibited waste connections

Storm Drainage

Storm drainage systems remove rainwater from roofs and other approved surfaces.

Study subjects may include:

• Roof drainage areas
• Rainfall rates
• Roof drains
• Gutters
• Leaders and conductors
• Horizontal storm piping
• Secondary drainage
• Overflow drains
• Scuppers
• Discharge locations
• Combined systems where permitted

Storm Drainage Calculations

Storm drainage sizing may depend on roof area, rainfall rate, pipe slope, gutter size, and conductor capacity.

Candidates should practice:

• Calculating roof drainage areas
• Dividing roofs among multiple drains
• Using rainfall-rate tables
• Sizing roof drains
• Sizing vertical conductors
• Sizing horizontal storm piping
• Evaluating secondary drainage capacity
• Sizing gutters and scuppers

Plumbing Plan Reading

Plan-reading questions may require candidates to interpret plumbing drawings, riser diagrams, fixture schedules, symbols, notes, and details.

Study subjects may include:

• Water piping plans
• Sanitary drainage plans
• Vent riser diagrams
• Storm drainage plans
• Fixture schedules
• Pipe sizes
• Pipe slopes
• Cleanout locations
• Valves and equipment
• Isometric drawings
• Plan symbols and abbreviations

Candidates should connect information shown on a plan with the corresponding plumbing code requirements.

Plumbing Isometric Drawings

Isometric drawings show the relationship between fixtures, drainage piping, vents, stacks, and branches.

Candidates should practice identifying:

• Fixture connections
• Drainage branches
• Soil and waste stacks
• Vent stacks
• Individual vents
• Wet vents
• Cleanouts
• Pipe sizes
• Changes in elevation
• Direction of flow

Plumbing System Testing

Plumbing systems may require testing before piping is concealed or placed into service.

Study areas may include:

• Water piping pressure tests
• Drainage and vent tests
• Water tests
• Air tests
• Vacuum tests where permitted
• Test pressure and duration
• Gauge selection
• Isolation of equipment
• Leak inspection
• Repair and retesting
• Inspection documentation

Plumbing Safety

Plumbing work may involve excavation, pressurized piping, hot work, power tools, confined spaces, ladders, and exposure to contaminated systems.

Important safety subjects may include:

• Personal protective equipment
• Trenching and excavation safety
• Confined-space awareness
• Hot-work precautions
• Pressure-test safety
• Lockout and tagout
• Ladder safety
• Material handling
• Sanitation and exposure control
• Protection of occupants and property

Code-Book Navigation

An open-book plumbing exam still requires fast and accurate reference navigation.

A practical lookup method includes:

• Read the complete question
• Identify the plumbing system involved
• Select the likely chapter
• Use the table of contents or index
• Locate the complete section or table
• Review definitions, exceptions, and footnotes
• Confirm that the provision applies to the stated conditions
• Record difficult subjects for additional practice

Candidates should practice using fixture-unit, water-supply, drainage, vent, and storm-drainage tables before exam day.

Organizing the G25-N Reference

A practical tab system may include:

• Definitions
• General regulations
• Fixtures
• Water heaters
• Water supply
• Backflow prevention
• Sanitary drainage
• Drainage tables
• Cleanouts
• Vents
• Vent tables
• Traps
• Interceptors
• Storm drainage
• Referenced standards

Candidates should verify current testing rules before adding tabs, highlighting, notes, or other modifications.

Recommended Study Plan

• Review exam rules and code-book organization
• Study plumbing definitions and general regulations
• Review approved materials and joints
• Study plumbing fixtures and water heaters
• Practice water-supply fixture-unit calculations
• Review backflow prevention
• Practice sanitary drainage sizing
• Study cleanout requirements
• Review vent types and vent sizing
• Study traps, interceptors, and separators
• Practice storm-drainage calculations
• Review plumbing plans and isometric drawings
• Complete timed code-navigation exercises
• Review every missed practice question

Which G25-N Package Should You Choose?

• Choose the Books & Courses Rental Package for temporary book access and structured online preparation.
• Choose the Highlighted & Tabbed Book Package for a professionally organized plumbing reference.
• Choose Online Exam Prep when you already own the correct code book and want guided study.
• Choose the Exam Book Package for independent preparation and permanent book ownership.

FAQ

Q. What is the ICC Journeyman Plumber - G25-N exam?

A. It is an ICC Contractor and Trades examination used by participating jurisdictions to evaluate journeyman-level plumbing code knowledge and installation skills.

Q. How much does the Books & Courses Rental Package cost?

A. The sale price is $540.00, reduced from the regular price of $840.00.

Q. How much does the Highlighted & Tabbed Book Package cost?

A. The sale price is $245.00, reduced from the regular price of $445.00.

Q. How much does Online Exam Prep cost?

A. The sale price is $295.00, reduced from the regular price of $395.00.

Q. How much does the Exam Book Package cost?

A. The sale price is $129.00, reduced from the regular price of $229.00.

Q. What book is included in the G25-N Exam Book Package?

A. Current package information identifies the 2018 International Plumbing Code.

Q. How many questions are on the G25-N examination?

A. Current product descriptions show different question totals. Candidates should confirm the official total in the bulletin for their scheduled examination.

Q. How much time is allowed?

A. Current product descriptions show different testing limits. Verify the current time allowance before scheduling the examination.

Q. Is the G25-N examination open book?

A. Current package information describes the examination as open book. Candidates must follow current rules for approved references, tabs, highlighting, notes, and book condition.

Q. What subjects should I study?

A. Study general regulations, fixtures, water heaters, water supply, backflow prevention, sanitary drainage, vents, traps, interceptors, storm drainage, testing, and plan reading.

Q. Should I practice water pipe-sizing calculations?

A. Yes. Candidates should practice fixture units, developed length, available pressure, elevation loss, and pipe-sizing tables.

Q. Should I practice drainage calculations?

A. Yes. Review drainage fixture units, pipe slopes, branch sizing, stack sizing, building drains, and building sewers.

Q. Should I study vent sizing?

A. Yes. Vent questions may involve fixture units, developed length, trap arms, wet venting, and vent terminations.

Q. Should I study plumbing plans?

A. Yes. Candidates should practice reading plans, riser diagrams, isometric drawings, fixture schedules, pipe sizes, and slopes.

Q. Does passing G25-N automatically issue a plumbing license?

A. No. The applicable licensing authority controls experience, applications, supervision, fees, insurance, and final approval.

Q. Where can I purchase the G25-N packages?

A. The available options can be found in the ICC Journeyman Plumber - G25-N exam prep collection.

Conclusion

The ICC Journeyman Plumber - G25-N examination requires candidates to combine practical plumbing experience with efficient navigation of the International Plumbing Code.

Important preparation subjects include plumbing fixtures, water heaters, water supply, backflow prevention, sanitary drainage, venting, traps, interceptors, storm drainage, plan reading, testing, and safety.

1 Exam Prep offers a Books & Courses Rental Package, Highlighted & Tabbed Book Package, Online Exam Prep, and Exam Book Package for different preparation needs and budgets.

Shop ICC Journeyman Plumber - G25-N Exam Prep

Key Takeaways

• G25-N is the ICC National Standard Journeyman Plumber examination path.
• The Books & Courses Rental Package sale price is $540.00.
• The Highlighted & Tabbed Book Package sale price is $245.00.
• The Online Exam Prep sale price is $295.00.
• The Exam Book Package sale price is $129.00.
• The current package reference is the 2018 International Plumbing Code.
• The examination is described as open book under current testing rules.
• Current product descriptions show conflicting question totals and time limits.
• Candidates should verify the current examination bulletin before registering.
• Major subjects include fixtures, water supply, drainage, venting, traps, storm drainage, and plan reading.
• Passing G25-N does not automatically issue a plumbing license.