Idaho Plumbing Journeyman • PSI • 100-Point Exam • 180 Minutes • 70 Points to Pass • Open Book
Ready to become a licensed journeyman plumber in Idaho? This Idaho Journeyman Plumber Contractor Exam Prep guide explains the state's plumbing license requirements, PSI examination, approved Uniform Plumbing Code references, drainage and vent systems, water supply, plumbing calculations, schematic sizing, and helpful study products from Contractor Exam Preps.
Idaho licenses journeyman plumbers through the Idaho Division of Occupational and Professional Licenses (DOPL) and the Idaho State Plumbing Board.
The official examination is called the Plumbing Journeyman Exam.
Its purpose is to evaluate a candidate's ability to interpret plumbing requirements and apply the correct rules to common plumbing installations.
A journeyman plumber works with water supply piping, sanitary drainage, waste systems, vents, plumbing fixtures, water heaters, traps, cleanouts, and other piping systems.
Some projects involve residential homes.
Others involve commercial buildings, schools, offices, restaurants, apartment complexes, and industrial facilities.
In every setting, plumbing systems must deliver clean water and remove wastewater safely.
The Idaho examination tests knowledge of the state's plumbing code rather than simply asking whether someone has worked around pipes for several years.
The current PSI Candidate Information Bulletin, effective December 10, 2025, identifies a 100-point Plumbing Journeyman examination with 180 minutes allowed.
The minimum passing score is 70 points.
The exam is open book.
Unlike examinations where a testing center supplies the code reference, Idaho's plumbing candidates are responsible for bringing their own approved books.
The official PSI bulletin lists the 2015 Uniform Plumbing Code (UPC) and 2017 Idaho State Plumbing Code (ISPC) as the allowed plumbing references.
These are the correct editions to study for the current Idaho examination.
Using a newer codebook simply because it was published recently is not the best strategy when the official exam references an older edition.
The exam blueprint covers Idaho State Plumbing Code chapters 1 through 12, as well as selected chapters 14 through 17.
It also includes two special plumbing sizing questions based on schematics supplied during the examination.
These schematic questions are worth four points each.
That means candidates must pay special attention to plumbing mathematics, drawings, fixture units, and pipe sizing.
Correctly answering one sizing question can carry more scoring weight than one standard code question.
The exam bulletin labels the exam as 100 questions, while its detailed breakdown includes two four-point schematic items within a 100-point total.
Use the official scoring rules and do not treat every listed item as necessarily having equal point value.
Idaho offers more than one way to qualify for journeyman plumbing licensure.
The traditional apprenticeship pathway includes 8,000 supervised plumbing work hours and four years of approved schooling.
The training involves approximately 576 hours of approved classroom instruction, usually divided into 144 hours per school year.
An alternative work-experience pathway allows applicants with 16,000 hours of qualifying supervised plumbing experience to seek licensure without using the same classroom pathway.
Applicants must document the experience and satisfy the state requirements for the pathway they use.
Idaho's official licensing instructions also explain reciprocity pathways for qualified plumbers from Montana, Oregon, and Washington.
Reciprocity is not automatic.
Applicants must meet the state-specific verification and eligibility conditions.
After satisfying examination eligibility and passing the required test, the applicant submits the journeyman licensing application through Idaho DOPL.
It is important to distinguish the Journeyman Plumber license from the separate Plumbing Contractor license.
A journeyman license qualifies an individual for plumbing work within the applicable rules.
A Plumbing Contractor license is required for regulated independent plumbing contracting activities.
The contractor examination is different from the journeyman examination.
It includes business-and-law questions and has a four-hour time limit with a 75-point passing requirement.
Confusing the two examinations can lead to buying the wrong books or preparing for the wrong test.
For the correct Idaho journeyman codebook, Contractor Exam Preps offers the Idaho Journeyman Plumber Exam Book Package.
This product includes the 2015 Uniform Plumbing Code, which is one of the approved reference books for the current Idaho Plumbing Journeyman examination.
The retailer also offers a Journeyman Plumber Study Guide Based on the 2021 UPC and a Journeyman Plumber Online Course Based on the 2021 UPC.
These newer resources may support broader Uniform Plumbing Code education, plumbing math, and practice questions.
However, they use the 2021 UPC, not the 2015 UPC specified for Idaho's current PSI examination.
For Idaho-specific testing, the 2015 UPC product should be the main codebook recommendation.
Use newer study materials only with awareness of the edition differences.
This complete guide includes the licensing pathway, exam snapshot, official chapter breakdown, detailed PSI specifications, study strategy, plumbing diagram, eight-step licensing roadmap, exam-weighting graphics, product guide, six-week study plan, credential illustration, interactive FAQs, and a related 1ExamPrep video.
Important Idaho Journeyman Plumber 2026 Update: The official Idaho PSI bulletin, effective December 10, 2025, lists the Plumbing Journeyman examination at 100 points, 180 minutes, and a minimum passing score of 70 points. The exam is open book, and candidates bring the approved 2015 Uniform Plumbing Code and/or 2017 Idaho State Plumbing Code. Permanent indexing, highlighting, and underlining may be prepared before testing. Temporary markers, loose notes, and writing during the exam are prohibited. Some older commercial product descriptions incorrectly list a four-hour time limit and 75% passing requirement for the Journeyman exam. Those figures match the separate Plumbing Contractor examination, not the current Journeyman examination. Always follow the official Idaho DOPL and PSI bulletin.
An Idaho Journeyman Plumber is a plumbing tradesperson who has completed the qualifying education or experience pathway and passed the examination required for state licensure.
Journeyman plumbers work on systems that provide potable water to buildings and safely remove wastewater.
These systems are important for homes, offices, schools, stores, restaurants, and many other buildings.
Idaho plumbers may work with copper piping, plastic drainage materials, water heaters, fixtures, valves, sanitary drainage systems, vents, and underground building sewers.
Each material and system has its own installation requirements.
For example, the correct water supply pipe size depends on fixture demand and available pressure.
Drainage pipe sizing depends on the type and number of connected plumbing fixtures.
Venting must protect trap seals and help drainage systems function correctly.
Traps help prevent sewer gases from entering buildings.
Cleanouts provide access to piping for maintenance and clearing blockages.
Water heaters require suitable installation and safety protection.
These requirements are covered by Idaho's adopted plumbing code.
Idaho currently identifies the 2017 Idaho State Plumbing Code, based on the 2015 Uniform Plumbing Code, as its state plumbing code.
That is different from a state that uses the International Plumbing Code as its principal plumbing standard.
Using the wrong code family can lead to errors during exam preparation.
The Idaho Plumbing Journeyman exam tests code knowledge across several chapters.
It also tests how candidates apply plumbing sizing principles to a schematic drawing.
That combination means students should prepare for both code navigation and practical calculations.
Field experience is valuable, but it should be supported by accurate knowledge of the official code.
A plumber may know how to install a particular fixture from experience.
However, the examination may ask the exact condition under which an installation method is permitted.
That condition may be hidden in a table note, exception, or definition.
Learning where to find the correct requirement is one of the most useful study skills.
Journeyman plumbers should also understand the limits of individual licensing.
Working as a licensed journeyman and independently offering plumbing contracts are different legal activities in Idaho.
Individuals who want to establish a plumbing contracting business must satisfy the separate contractor licensing requirements.
Official classification: Idaho Plumbing Journeyman.
Licensing authority: Idaho DOPL and State Plumbing Board.
Primary code: 2017 Idaho State Plumbing Code, based on the 2015 UPC.
Independent plumbing contracting: Separate contractor licensure required.
Review the Idaho State Plumbing Board for current licensing information.
Idaho has two principal qualification paths for Plumbing Journeyman applicants, as well as specific reciprocity arrangements for eligible out-of-state plumbers.
| Step | Requirement | What to Prepare |
|---|---|---|
| Choose License | Plumbing Journeyman | Confirm that you need the standard Journeyman license rather than a specialty or contractor license. |
| Identify Licensing Board | Idaho State Plumbing Board | Review the current Idaho DOPL requirements. |
| Traditional Apprentice Path | 8,000 Work Hours | Document qualifying supervised plumbing installation experience. |
| Traditional School Requirement | Four Years | Complete a Board-approved plumbing education program. |
| Classroom Education | 576 Hours | Complete approved instruction, normally 144 hours each academic year. |
| Experience-Only Path | 16,000 Work Hours | Document qualifying supervised plumbing installation experience. |
| Active Apprenticeship | Registration | Maintain required Idaho apprentice registration when accumulating in-state qualifying hours. |
| Experience Verification | Work Verification | Use the official state forms and records for the chosen qualification path. |
| Excluded Experience | Restrictions Apply | Pipefitting and appliance specialty work do not qualify as standard journeyman plumbing experience. |
| Out-of-State Path | Montana, Oregon, Washington | Review reciprocity eligibility and required license verification. |
| Exam Registration | PSI | Select the official Plumbing Journeyman examination. |
| Exam Format | Computer-Based | Practice multiple-choice questions and code lookups. |
| Exam Time | 180 Minutes | Practice completing the examination in three hours. |
| Passing Standard | 70 Points | Use the official PSI weighted scoring requirements. |
| Open Book | Yes | Bring only the approved code references. |
| Approved UPC | 2015 Edition | Use the proper Uniform Plumbing Code reference. |
| Approved State Code | 2017 ISPC | Review Idaho-specific amendments and rules. |
| Permanent Tabs | Permitted | Prepare compliant permanent reference indexing before the examination. |
| Highlighting | Permitted Before Exam | Mark important sections in advance according to PSI restrictions. |
| Temporary Notes | Prohibited | Do not insert removable notes, Post-it markers, or loose pages. |
| Writing During Exam | Prohibited in References | Do not write in your codebook during testing. |
| Pass Examination | PSI | Complete the test and obtain the official results. |
| Apply for License | DOPL | Submit the license application after meeting the qualifications and passing the examination. |
| License Renewal | Three-Year Term | Maintain the license and renew by its assigned expiration date. |
| Continuing Education | No Current CE Requirement | Monitor Idaho DOPL for future rule changes. |
The Idaho PSI Candidate Information Bulletin effective December 10, 2025, provides the following information for the Plumbing Journeyman examination.
| Exam Detail | Category | Official Information |
|---|---|---|
| Official Exam | PSI | Plumbing Journeyman Exam |
| Licensing State | State | Idaho |
| Licensing Agency | DOPL | Division of Occupational and Professional Licenses |
| Licensing Board | DOPL | Idaho State Plumbing Board |
| Testing Company | PSI | PSI Services |
| Examination Format | PSI | Computer-Based |
| Exam Heading | PSI | 100 Questions |
| Total Scoring Value | PSI | 100 Points |
| Time Limit | PSI | 180 Minutes |
| Passing Requirement | PSI | 70 Points |
| Open Book | PSI | Yes |
| Approved Reference One | Code | 2015 Uniform Plumbing Code |
| Approved Reference Two | Code | 2017 Idaho State Plumbing Code |
| Reference Responsibility | PSI | Candidate Brings Approved Books |
| Temporary Tabs | PSI | Not Permitted |
| Permanent Indexing | PSI | Permitted Before Examination |
| Pre-Exam Highlighting | PSI | Permitted |
| Writing During Exam | PSI | Not Permitted in References |
| Idaho Code Chapter 1 | Blueprint | 5 Items |
| Idaho Code Chapter 2 | Blueprint | 5 Items |
| Idaho Code Chapter 3 | Blueprint | 5 Items |
| Idaho Code Chapter 4 | Blueprint | 5 Items |
| Idaho Code Chapter 5 | Blueprint | 10 Items |
| Idaho Code Chapter 6 | Blueprint | 11 Items |
| Idaho Code Chapter 7 | Blueprint | 11 Items |
| Idaho Code Chapter 8 | Blueprint | 6 Items |
| Idaho Code Chapter 9 | Blueprint | 10 Items |
| Idaho Code Chapter 10 | Blueprint | 7 Items |
| Idaho Code Chapter 11 | Blueprint | 4 Items |
| Idaho Code Chapter 12 | Blueprint | 8 Items |
| Idaho Code Chapter 14 | Blueprint | 1 Item |
| Idaho Code Chapter 15 | Blueprint | 2 Items |
| Idaho Code Chapter 16 | Blueprint | 1 Item |
| Idaho Code Chapter 17 | Blueprint | 1 Item |
| Schematic Sizing | Blueprint | 2 Questions Worth 4 Points Each |
| Primary Experience Path | Licensing | 8,000 Hours and 576 Classroom Hours |
| Alternative Experience Path | Licensing | 16,000 Qualifying Work Hours |
| Reciprocity | Licensing | Specific Montana, Oregon and Washington Pathways |
| License Term | Licensing | Three Years |
| Continuing Education | Licensing | None Currently Required for Plumbing |
| Separate Contractor Exam | Contracting | 100 Questions, 240 Minutes, 75 Points Required |
Official PSI bulletin: Effective December 10, 2025.
Journeyman examination: 180 minutes and 70 passing points.
Schematic questions: Two items worth four points each.
Important scoring detail: The detailed blueprint totals 100 available points because of the weighted schematic questions.
Contractor examination: Different test with 240 minutes and 75-point passing requirement.
The current PSI blueprint organizes most questions by chapter of the 2017 Idaho State Plumbing Code.
Idaho uses the 2015 UPC as the underlying plumbing-code edition.
Review each topic using the appropriate Idaho code language and amendments.
Review permits, inspections, enforcement, application of the plumbing code, and administrative requirements. Study the rules that determine how plumbing installations are regulated.
Learn important plumbing terms. Understand the differences among drains, vents, building sewers, fixture branches, traps, cross-connections, and other technical definitions.
Review common requirements involving materials, installation, protection, testing, and general plumbing workmanship.
Study fixture requirements, fixture connections, approved fittings, materials, and installation conditions.
Review water heater installation, temperature control, safety valves, discharge piping, equipment support, and applicable code requirements.
Study water distribution piping, water pressure, pipe sizing, backflow prevention, valves, materials, fittings, and water demand. This is one of the largest examination chapters.
Review drainage fixture units, pipe sizing, fittings, slope, connections, cleanouts, and other sanitary waste requirements. This chapter has the same high question count as water supply.
Study air gaps, indirect connections, special discharge conditions, and indirect waste piping requirements.
Review trap venting, vent sizing, vent connections, common venting methods, and requirements that protect trap seals.
Study traps, trap arms, interceptors, separators, trap protection, and related drainage requirements.
Review roof drainage, stormwater piping, connections, and sizing concepts where applicable.
Study fuel gas systems, piping materials, sizing, installation, testing, and appliance-related requirements.
Review firestop requirements relevant to plumbing penetrations and protected assemblies.
Understand specialized water systems and code requirements for alternate water supplies.
Review the applicable concepts for rainwater catchment systems intended for nonpotable uses.
Understand how standards are referenced and used in the plumbing code.
The exam includes two schematic-based plumbing sizing questions.
Each schematic question is worth four points.
Practice tracing piping through a drawing, identifying connected fixtures, using fixture units, and determining appropriate pipe sizing.
This section deserves extra attention because of its weighted scoring.
Largest chapters: Water Supply and Distribution and Sanitary Drainage, 11 items each.
Next highest: Water Heaters and Vents, 10 items each.
Schematic sizing: Two questions, four points each.
Approved references: 2015 UPC and 2017 Idaho State Plumbing Code.
The most important first step is studying the right plumbing code.
Idaho's current Plumbing Journeyman exam uses the 2015 UPC and 2017 Idaho State Plumbing Code as its approved references.
Students should not automatically replace those books with newer UPC or IPC editions.
Once you have the correct code, study the organization of the chapters.
Learn where to find definitions, fixture requirements, water heater rules, water supply sizing, sanitary drainage, vents, and traps.
Then work through practice questions while locating the supporting rules.
Open-book preparation should focus on speed and accuracy.
A question might appear simple, but a small exception can change the answer.
Read the entire requirement before selecting a response.
Water Supply: Pipe sizing, fixture demand, valves, pressure, backflow, and distribution.
Sanitary Drainage: Drainage fixture units, pipe slope, sizing, connections, fittings, and cleanouts.
Vents: Venting methods, trap protection, and sizing.
Fixtures: Fixture installation, fittings, and water heater requirements.
Indirect Waste: Air gaps, indirect connections, and special discharge.
Fuel Gas: Piping and appliance-related requirements.
Plumbing Math: Measurements, conversions, fixture units, and sizing calculations.
Schematics: Reading diagrams and identifying the correct size for connected piping.
Spend extra time on the schematic-sizing questions.
Idaho's PSI bulletin assigns two questions to schematic sizing.
Each one is worth four points.
Practice reading an isometric or schematic drawing and tracing a piping system from one connected fixture to the next.
Identify where fixture demand increases.
Then determine how that affects the required size of the connected piping.
Be careful with measurement units.
An incorrect conversion can ruin an otherwise correct calculation.
Practice writing down the quantities before solving the problem.
Keep calculations organized and confirm each result.
Also practice with the books prepared according to the exam rules.
Permanent indexing and highlighting can help with navigation.
However, temporary tabs and inserted loose paper are prohibited.
Do not develop a study system that depends on material you cannot bring into the exam.
Contractor Exam Preps' Idaho Journeyman Plumber Exam Book Package supplies the approved 2015 UPC reference.
For additional practice, the store also offers a 2021 UPC Journeyman Plumber Study Guide.
That study guide contains 990 practice questions, plumbing mathematics, and isometric analysis.
Because it is based on the 2021 UPC, use it as supplemental education rather than a replacement for Idaho's approved code.
Each week, complete a timed practice set and review missed answers.
When you miss a question, find the correct code section and understand what you overlooked.
This approach turns a mistake into a useful learning opportunity.
Plumbing schematics are a valuable part of Idaho exam preparation because two official examination questions involve sizing from supplied diagrams.
Simplified educational diagram. Not a code-approved installation plan or a substitute for official plumbing drawings.
Use these eight steps to move from plumbing experience toward your official Idaho Journeyman license.
Review Idaho DOPL requirements and make sure you are preparing for the standard Journeyman license rather than a specialty or contractor classification.
Use the 8,000-hour apprenticeship and approved schooling route or the 16,000-hour qualifying experience route.
Gather apprentice registration, education records, work verification, and licensed-supervision documentation.
Study the 2015 UPC and 2017 Idaho State Plumbing Code, following the open-book preparation rules.
Use Idaho's current testing process to select the Plumbing Journeyman exam and schedule an appointment.
Review water heaters, water distribution, drainage, vents, fixtures, fuel gas, calculations, and the weighted schematic questions.
Meet the 70-point passing standard within the 180-minute time limit.
Submit the license application through DOPL after completing the required qualifications and passing the examination. Maintain the license and consider contractor licensing if your goal is business ownership.
The bars represent each chapter's contribution to the official 100-point PSI exam blueprint. The two schematic questions contribute eight points combined.
Official total: 100 available points.
Code chapter items: 92 single-point items.
Schematic items: Two questions worth four points each, totaling eight points.
Passing requirement: 70 points.
Largest combined technical areas: Water supply, sanitary drainage, water heaters, and vents.
Idaho's Plumbing Journeyman exam is based on the UPC family of codes, not the IPC.
The official examination reference list identifies the 2015 UPC and 2017 Idaho State Plumbing Code.
Use those editions as the main source for examination-specific answers.
| Book or Study Material | Edition | Recommended Use |
|---|---|---|
| Uniform Plumbing Code | 2015 | Official approved Idaho Plumbing Journeyman exam reference. |
| Idaho State Plumbing Code | 2017 | Official state plumbing code and approved exam reference. |
| Idaho Journeyman Plumber Exam Book Package | 2015 UPC | Idaho-specific Contractor Exam Preps product containing the approved UPC. |
| Journeyman Plumber Study Guide | 2021 UPC | Supplemental plumbing trade education and practice questions, not the approved Idaho test reference. |
| Journeyman Plumber Test Success Online Course | 2021 UPC | Supplemental video instruction, simulated exams, plumbing math, and isometrics. |
| Uniform Plumbing Code | 2024 | Newer-code education. Not listed as an approved Idaho Journeyman examination reference. |
| Plumbing Sizing Charts | Applicable 2015 UPC / Idaho Code | Fixture unit and water supply or drainage sizing practice. |
| Plumbing Isometric and Schematic Exercises | Educational Resources | Practice drawing interpretation and the two weighted schematic questions. |
| Idaho PSI Candidate Information Bulletin | Effective December 2025 | Official examination time, passing score, chapter breakdown, and allowed materials. |
| Idaho DOPL Journeyman Application | Current Official Form | Eligibility pathways, work verification, reciprocity, and licensing application. |
| Idaho Contractors Business and Law Reference Manual | Current | Relevant to the separate Plumbing Contractor exam, not the standard Journeyman exam. |
Best Idaho-specific reference: 2015 UPC.
Official state code: 2017 Idaho State Plumbing Code.
Supplemental study option: 2021 UPC courses and practice guides.
Do not substitute: Newer code editions or IPC references for the official Idaho exam-approved materials.
Idaho allows candidates to bring the approved plumbing references into the examination room.
However, the testing rules are specific.
Permanent indexing, highlighting, and underlining are permitted when completed before the exam.
Temporary markers and loose papers are prohibited.
Candidates may not write in their reference books during the examination.
Open book: Yes.
Bring your own references: Yes.
Approved editions: 2015 UPC and 2017 ISPC.
Permanent indexing: Permitted.
Loose notes: Prohibited.
Writing during examination: Prohibited in references.
An Idaho Journeyman Plumber may perform qualifying plumbing work within the scope of the state license and applicable plumbing rules.
Common work involves installing, repairing, and maintaining plumbing systems that provide water and remove wastewater.
Plumbers may work with supply piping, fixtures, drains, vents, water heaters, water service systems, and related equipment.
In residential buildings, this may involve sinks, lavatories, tubs, showers, toilets, water heaters, and associated piping.
Commercial work may involve larger fixture groups, special equipment, and more complicated water distribution or sanitary drainage installations.
Some projects require plumbing plan review and permits.
Other work may involve inspections during installation and after completion.
The actual requirements depend on the nature and location of the work.
Idaho's plumbing code must be followed when designing or installing regulated plumbing systems.
Journeyman plumbers should also understand supervision requirements for apprentices.
Apprentices must work within the registration and supervision rules that apply to their training.
Idaho does not count unlicensed plumbing work toward qualifying apprenticeship hours when the law requires active registration.
Proper records are important for future journeyman applicants.
There is another licensing distinction for business owners.
An individual Plumbing Journeyman license does not automatically authorize operating an independent plumbing contracting business.
Plumbing Contractors must satisfy separate licensing requirements.
The contractor application generally requires an active Idaho Journeyman license, passage of the designated contractor examination, and proof of a $2,000 surety bond.
Unlike the Journeyman exam, the Plumbing Contractor examination includes business-and-law content.
Its current PSI bulletin lists 100 questions, 240 minutes, and a 75-point passing requirement.
Contractor preparation therefore includes both plumbing trade knowledge and business management concepts.
It may involve estimating, contracts, licensing responsibilities, financial management, and project administration.
Individuals planning to operate a plumbing business should review these requirements separately.
Journeyman license: Individual plumbing trade qualification.
Plumbing Contractor license: Separate authority for regulated independent contracting.
Contractor exam: Includes business-and-law content.
Contractor bond: $2,000 surety bond.
| Classification | Licensing Authority | Main Requirement or Purpose |
|---|---|---|
| Plumbing Apprentice | Idaho DOPL | Registration and qualifying supervised plumbing training. |
| Journeyman Apprentice Path | Idaho State Plumbing Board | 8,000 supervised work hours and four years of approved schooling. |
| Classroom Instruction | Approved Programs | 576 approved instruction hours in the apprenticeship pathway. |
| Journeyman Experience Path | Idaho DOPL | 16,000 qualifying supervised plumbing work hours. |
| Journeyman Plumbing License | Idaho State Plumbing Board | Individual journeyman plumbing work qualification. |
| Plumbing Specialty Journeyman | Idaho State Plumbing Board | Separate restricted plumbing specialty classification. |
| Journeyman Plumbing Exam | PSI | 100 available points, 180 minutes, 70 points to pass. |
| Plumbing Specialty Exam | PSI | Separate examination based on the applicable specialty classification. |
| Plumbing Contractor | Idaho State Plumbing Board | Separate license for regulated plumbing contracting. |
| Plumbing Contractor Exam | PSI | 100 questions, 240 minutes, 75 points to pass. |
| Plumbing Contractor Bond | Idaho DOPL | $2,000 surety bond. |
| Journeyman Reciprocity | Idaho DOPL | Specific pathways involving Montana, Oregon and Washington. |
| Journeyman Renewal | Idaho DOPL | Three-year license term. |
| Continuing Education | Idaho DOPL | No current plumbing CE requirement. |
Apprentice: Works and trains under applicable registration and supervision requirements.
Journeyman: Holds an individual plumbing license.
Plumbing Contractor: Holds separate contracting authority with additional examination and bonding requirements.
8,000 Hours and 576 Classroom Hours
16,000 Qualifying Plumbing Hours
180 Minutes and 70 Passing Points
Reciprocity: Montana, Oregon and Washington have specific eligibility and verification requirements.
Licensure: Passing the exam is one requirement, but DOPL must also confirm the applicant's qualifications.
Use this study schedule to prepare for Idaho's official code-based, open-book examination and its weighted schematic questions.
The Idaho Plumbing Journeyman examination can be challenging because it requires knowledge of plumbing code provisions, calculations, and schematic interpretation.
Having years of field experience provides a useful foundation.
However, an exam may ask questions differently than a supervisor would ask them on a jobsite.
Instead of asking how to install a particular pipe, the examination may ask which plumbing-code condition applies.
A small change in fixture demand, pipe size, or installation location can change the correct answer.
The open-book format helps, but it does not eliminate the need to study.
Candidates have only 180 minutes to complete the official examination.
Searching through an unfamiliar codebook for every question can waste a great deal of time.
The best approach is to know the chapter organization before testing.
Identify the subject of a question and go directly to the relevant section.
Then check the code requirement, including exceptions, notes, and sizing tables.
Water supply and sanitary drainage deserve extra study time.
These are the two largest chapters in the official exam blueprint, with eleven items each.
Water heaters and venting follow with ten items each.
Together, these subjects account for a substantial portion of the examination.
Plumbing schematic sizing is another important area.
Two questions are worth four points each.
A candidate who overlooks these questions may give up eight available points.
Practice reading diagrams until you can identify connected fixtures and determine the relevant sizing requirements.
Plumbing math should be practiced regularly.
Work through measurements and conversions carefully.
Learn to recognize whether the problem involves supply piping, drainage piping, or another system.
Be especially careful when the question asks for minimum pipe size or a specific code condition.
Another common preparation mistake is using the wrong codebook.
Idaho's approved exam references are the 2015 UPC and 2017 Idaho State Plumbing Code.
Newer UPC editions and IPC guides may teach useful general plumbing concepts, but they are not listed as official references for this examination.
That is why the Idaho Journeyman Plumber Exam Book Package is an especially relevant store product.
It includes the correct 2015 UPC reference for open-book study.
Supplemental tools such as the UPC Journeyman Plumber Online Course may help with broader trade concepts and isometric practice.
However, those 2021 UPC resources should not replace the examination-approved 2015 UPC.
With a clear codebook, a structured study plan, repeated calculations, and timed practice, the examination becomes easier to manage.
Official test: Idaho Plumbing Journeyman.
Time: 180 minutes.
Passing: 70 points.
References: 2015 UPC and 2017 ISPC.
Open-book preparation: Permanent tabs and highlighting permitted before testing.
Contractor Exam Preps offers an Idaho-specific 2015 UPC book package as well as supplemental UPC-based study materials.
The Idaho-specific book package is the strongest match for the current official PSI reference list.
The other products below are useful for broader plumbing education but use a newer UPC edition.
Idaho Exam Reference | 2015 UPC
Supplemental UPC Trade Review
Supplemental Online Plumbing Instruction
Recommended Idaho exam book: 2015 UPC package.
Required exam edition: 2015 UPC and 2017 Idaho State Plumbing Code.
Supplemental guides and course: Based on the 2021 UPC and intended for additional learning.
Current Idaho DOPL bulletin takes priority: 180 minutes, 70 passing points, and two four-point schematic questions.
Important: Some seller descriptions contain older or incorrect timing and passing figures. Follow the official PSI bulletin instead.
Actual Idaho Journeyman Plumber product artwork hosted by ContractorExamPreps.com. The educational credential above is not a state-issued license.
This custom educational credential features an Idaho state outline, a water droplet, plumbing pipes, a valve, and the state's official journeyman plumbing exam-preparation topic.
It represents study preparation only and is not an official license or proof of examination passage.
The adjacent product image is served directly by ContractorExamPreps.com and links to its Idaho Journeyman Plumber Exam Book Package.
• Idaho Plumbing Journeyman
• Idaho State Plumbing Board
• Division of Occupational and Professional Licenses
• PSI Examination
• 100 Available Points
• 180-Minute Time Limit
• 70-Point Passing Requirement
• Open-Book Examination
• 2015 Uniform Plumbing Code
• 2017 Idaho State Plumbing Code
• Idaho Plumbing Amendments
• Plumbing Code Definitions
• General Regulations
• Plumbing Fixtures and Fittings
• Water Heater Installation
• Water Supply and Distribution
• Backflow Prevention
• Pipe Sizing
• Sanitary Drainage
• Drainage Fixture Units
• Indirect Waste Systems
• Sanitary Vents
• Traps and Interceptors
• Storm Drainage
• Fuel Gas Piping
• Referenced Standards
• Firestop Protection
• Alternate Water Sources
• Nonpotable Rainwater Catchment
• Plumbing Mathematics
• Schematic Sizing
• Weighted Exam Questions
• Plumbing Isometric Diagrams
• Approved Reference Indexing
• Permanent Codebook Tabs
• PSI Test-Day Preparation
• Idaho Apprenticeship Pathway
• 8,000-Hour Experience Path
• 576 Classroom Hours
• 16,000-Hour Experience Path
• Idaho Journeyman Reciprocity
• Separate Plumbing Contractor Licensing
Build your plumbing code knowledge and codebook navigation skills using the correct Idaho-approved UPC edition.
Idaho Journeyman Plumbing Licensing
The Idaho Division of Occupational and Professional Licenses administers plumbing licensing through the Idaho State Plumbing Board.
The standard apprenticeship pathway requires 8,000 supervised work hours and four years of approved instruction. Another pathway requires 16,000 qualifying supervised work hours.
The traditional route requires 576 hours of approved plumbing instruction, usually 144 hours per year for four years.
Idaho recognizes a 16,000-hour qualifying supervised experience pathway. Applicants must meet the state's verification and eligibility requirements.
No. Idaho's licensing instructions specifically exclude pipefitting and appliance plumbing specialty work from standard journeyman plumbing experience qualifications.
Qualifying work completed in Idaho generally requires active apprentice registration where applicable. Unlicensed work does not automatically count toward the required hours.
Yes. Idaho identifies reciprocity pathways involving Montana, Oregon, and Washington, subject to experience, active license, examination, and other verification requirements.
DOPL's current initial licensing instructions direct candidates to meet the qualifications and pass the required examination before submitting their Journeyman license application.
Idaho PSI Journeyman Plumber Exam
PSI administers the official Plumbing Journeyman examination for Idaho DOPL.
PSI labels the examination as 100 questions. Its detailed scoring blueprint totals 100 points, including two schematic questions worth four points each.
180 minutes, or three hours, according to the PSI bulletin effective December 10, 2025.
The minimum passing score is 70 points under the official current PSI bulletin.
Some commercial descriptions contain outdated or mismatched information. Idaho's separate Plumbing Contractor examination is 240 minutes and requires 75 points. The current Journeyman examination is 180 minutes and requires 70 points.
Yes. Approved plumbing references are allowed, and the candidate must bring them to the examination center.
Yes. PSI assigns four points to each of the two schematic-sizing questions, for eight possible points combined.
Idaho Plumbing Code References
Idaho's current adopted 2017 State Plumbing Code is based on the 2015 Uniform Plumbing Code.
The official PSI bulletin lists the 2015 Uniform Plumbing Code and 2017 Idaho State Plumbing Code as approved references.
The 2024 UPC is not listed among the approved exam references. Candidates should use the editions specified by the current PSI bulletin.
No. Idaho's official approved references are based on the UPC family, not the 2021 IPC.
No. Idaho Plumbing Journeyman candidates must bring their own approved references.
Permanent indexing is permitted when prepared before the examination and compliant with PSI's rules.
Yes. Pre-exam highlighting and underlining are permitted.
No. Temporary markers and additional loose papers are prohibited by PSI.
No. Writing in reference materials during the examination is prohibited.
Plumbing Exam Subjects
Water Supply and Distribution and Sanitary Drainage contain eleven items each, followed by Water Heaters and Vents with ten items each.
Yes. Chapter 5 contains ten items in the official blueprint.
Yes. Chapter 7 contains eleven items, making it one of the largest sections.
Chapter 9 contains ten items.
Yes. Chapter 12 contains eight items covering fuel gas piping requirements.
Practice tracing fixture connections, identifying fixture units, using approved code tables, and determining pipe sizes from drawings.
Idaho Journeyman and Contractor Licensing
A Journeyman license alone does not replace the separate Idaho Plumbing Contractor license required for regulated contracting.
The current PSI Plumbing Contractor examination is 240 minutes, or four hours.
The contractor examination requires 75 points. This should not be confused with the Journeyman examination's 70-point requirement.
Yes. The Idaho Plumbing Contractor application identifies a $2,000 surety bond requirement.
Yes. The separate contractor exam includes business-and-law topics in addition to plumbing code and sizing content.
Renewal and Study Products
The standard Idaho Plumbing Journeyman license term is three years. Renew by the expiration date assigned to your license.
Idaho DOPL currently states that plumbing licensees do not have a continuing education requirement. Monitor the Board for future changes.
Yes. The Idaho Journeyman Plumber Exam Book Package includes the 2015 UPC listed among the state's approved PSI references.
Yes. Contractor Exam Preps sells a 2021 UPC study guide with 990 practice questions. It is supplemental study material, not the approved 2015 Idaho exam reference.
Yes. Online review can help with trade concepts, calculations, and schematic reading, but candidates should use the official Idaho reference editions for exam-specific answers.
No. Study materials support preparation, but candidates must meet the official state qualifications, pass the examination, and complete licensing requirements.
Watch this related 1ExamPrep YouTube video about Journeyman Plumber exam preparation, plumbing code study, water supply, drainage, fixtures, piping, vents, water heaters, and study strategies.
The video covers general plumbing examination preparation across states. Idaho candidates should apply these strategies to their own official 2015 UPC and 2017 Idaho State Plumbing Code requirements.
Video: Pass the 2026 Journeyman Plumber Exam.
Channel: 1ExamPrep.
Published: June 22, 2026.
Topics: Plumbing code, water supply, drainage, vents, fixtures, piping systems, water heaters, and exam study methods.
Idaho-specific reminder: Use the approved 2015 UPC and 2017 ISPC references.
Official exam: 180 minutes, 70 points required.
Use these Idaho plumbing licensing resources, actual Contractor Exam Preps product pages, and official PSI examination materials to prepare accurately.
Idaho licensing authority: DOPL and Idaho State Plumbing Board.
Exam: Plumbing Journeyman.
Time: 180 minutes.
Passing: 70 points.
Approved code references: 2015 UPC and 2017 ISPC.
Qualification paths: 8,000 hours with approved schooling, or 16,000 qualifying hours.
License term: Three years.
Contractor license: Separate requirements, examination, and bond.
Preparing for the Idaho Journeyman Plumber examination is an important step for plumbing professionals who want to earn their state trade license.
The Idaho State Plumbing Board and Division of Occupational and Professional Licenses regulate the licensing process.
Applicants must complete the appropriate plumbing experience and education requirements before receiving a license.
Idaho offers two primary qualification pathways.
The traditional apprenticeship route includes at least 8,000 hours of supervised plumbing work and four years of Board-approved plumbing education.
That education generally totals 576 classroom hours.
The alternative work-experience pathway requires 16,000 qualifying supervised plumbing work hours.
Both pathways involve appropriate documentation, and applicants must satisfy the state's specific experience requirements.
Idaho also maintains reciprocity arrangements for qualified plumbers from Montana, Oregon, and Washington.
Reciprocity applicants must meet the relevant conditions and provide the necessary verification.
After qualifying, candidates must pass the official Idaho Plumbing Journeyman examination.
The test is administered by PSI.
According to the current PSI Candidate Information Bulletin, effective December 10, 2025, the examination has 100 available scoring points and a time limit of 180 minutes.
The minimum passing score is 70 points.
The exam is open book, but candidates must bring their own approved plumbing references.
The official allowed books are the 2015 Uniform Plumbing Code and the 2017 Idaho State Plumbing Code.
These editions are particularly important because newer plumbing books may use different section numbering and requirements.
Students should not assume that a 2021 or 2024 UPC reference is automatically accepted during the Idaho examination.
The official blueprint covers Idaho State Plumbing Code chapters 1 through 12 and selected chapters 14 through 17.
Important topics include water supply and distribution, sanitary drainage, vents, water heaters, fixtures, indirect waste, traps, fuel gas piping, storm drainage, and related regulations.
The largest chapters are Water Supply and Sanitary Drainage, with eleven items each.
Water Heaters and Vents follow with ten items each.
Candidates should review these topics carefully, but the smaller chapters also contribute to the final score.
The examination also includes two plumbing schematic-sizing questions.
Each of these questions is worth four points.
That makes them especially valuable during the examination.
Students should practice reading plumbing drawings, identifying connected fixtures, determining fixture units, and calculating appropriate piping sizes.
Plumbing math and schematic interpretation deserve regular study time rather than a quick review the night before testing.
Open-book preparation requires good reference-navigation habits.
Students should learn the organization of the 2015 UPC and develop a reliable method for finding code requirements quickly.
The official rules permit permanent indexing, highlighting, and underlining completed before the examination.
Temporary markers, loose paper, and writing in reference materials during testing are prohibited.
That means candidates should prepare their books carefully and practice with an exam-compliant setup.
Contractor Exam Preps offers the Idaho Journeyman Plumber Exam Book Package, which contains the approved 2015 UPC.
This is a strong starting point for Idaho-specific exam preparation.
Other store products include a Journeyman Plumber Study Guide Based on the 2021 UPC and a Journeyman Plumber Online Course Based on the 2021 UPC.
These newer products can support general plumbing education, calculations, and isometric practice.
However, their 2021 UPC content should be treated as supplemental study material rather than the official Idaho examination reference.
Another important point is the difference between a Journeyman Plumber license and a Plumbing Contractor license.
A journeyman license is an individual trade qualification.
Independent regulated plumbing contracting requires separate state licensing.
The Idaho Plumbing Contractor examination has a different format, including business-and-law topics.
Its current PSI bulletin lists 240 minutes and a 75-point passing requirement.
Contractor licensure also involves a $2,000 surety bond and other state requirements.
Applicants should prepare for the correct license rather than assuming the journeyman and contractor examinations are interchangeable.
With qualifying experience, accurate records, the correct UPC references, consistent plumbing math review, and realistic timed practice, Idaho journeyman candidates can build a stronger understanding of the examination.
The goal is not simply to memorize answers.
It is to learn how plumbing systems work, recognize what each question is asking, and apply the correct code requirement efficiently.
That knowledge supports both examination preparation and professional plumbing work.
Find Idaho plumbing reference books, journeyman study guides, online courses, and contractor exam preparation resources at ContractorExamPreps.com.
