Colorado State Plumbing Board • PSI • 120 Scored Questions • 270 Minutes
Prepare for the Colorado Master Plumber Contractor Exam with a practical study plan covering plumbing codes, sanitary drainage, venting, water supply, storm drainage, fixtures, water heaters, isometric drawings, backflow prevention, system calculations, and advanced plumbing installations.
The Colorado Master Plumber license is issued by the Colorado State Plumbing Board, part of the Department of Regulatory Agencies, commonly called DORA.
The state licensing examination is administered by PSI. The current examination outline lists 120 scored questions and allows 270 minutes, or four hours and 30 minutes.
PSI may include up to 10 additional unscored questions, with as much as 30 minutes of extra testing time.
The published PSI bulletin lists 70% or 84 correct scored answers to pass. However, Colorado DORA's application information has also displayed a 75% passing requirement. Applicants should confirm the current score standard with PSI and the State Plumbing Board before testing.
The Colorado Master Plumber examination uses the International Plumbing Code (IPC) and the International Residential Code (IRC).
As of October 2026, the detailed PSI bulletin lists the 2021 IPC and 2021 IRC. Testing information indicates a transition to the 2024 editions effective November 1, 2026. Confirm the code edition for your scheduled exam.
The exam is reference-assisted, but you do not bring your personal codebooks. PSI provides approved IPC and IRC books at the testing center. Candidates cannot highlight, tab, underline, index, or write in those supplied books.
Contractor Exam Preps offers a dedicated Colorado Master Plumber Online Exam Prep Course covering plumbing knowledge and exam-style practice.
For independent code study, the store also offers the 2021 International Plumbing Code and the 2021 International Residential Code.
Colorado Master Plumber candidates should understand an additional licensing distinction. A personal Master Plumber license and a Plumbing Contractor business registration are separate state requirements.
This guide explains the exam, licensing experience, code editions, official topic weighting, useful study materials, and business registration rules.
Important 2026 Colorado Master Plumber update: The PSI Master Plumber examination currently has 120 scored questions and a 270-minute scored-test limit. The available PSI bulletin lists 70%, or 84 correct, as the passing line, while DORA's licensing application information has also displayed 75%. Confirm your actual passing requirement before testing. The PSI reference list uses the 2021 IPC and IRC in October 2026, with a reported transition to the 2024 editions on November 1, 2026. Testing-center codebooks are supplied by PSI. Personal highlighted or tabbed books are not permitted. Also remember that an individual Master Plumber license does not automatically complete the separate Plumbing Contractor business registration.
A Colorado Master Plumber is an experienced plumbing professional who has met the State Plumbing Board's advanced licensing requirements.
The Master Plumber credential represents the highest of Colorado's three main individual plumbing license levels.
The other levels are Residential Plumber and Journeyworker Plumber.
Master plumbers need strong knowledge of plumbing codes, system design, drainage, water supply, venting, fixtures, backflow prevention, testing, and safe installation methods.
They may work on residential, commercial, and other plumbing systems within the limits of Colorado law.
Master-level responsibilities can include supervising apprentices, reviewing installations, planning plumbing systems, and ensuring that plumbing work follows code requirements.
Some plumbing work requires reviewing complex layouts before any pipe is installed.
A master plumber may need to determine pipe sizes, evaluate water demand, inspect drainage slopes, select venting methods, and identify cross-connection hazards.
Colorado requires five full-time years, or 8,500 hours, of qualifying practical plumbing experience for the Master Plumber license.
The experience must be supported by the records and employer verification required by the State Plumbing Board.
Applicants cannot simply write their own experience letters and certify that everything is correct. DORA requires proper verification, including employer affidavits where applicable.
Once the applicant meets the licensing qualifications and examination requirements, the Board may issue the Master Plumber license.
However, the individual license is different from registering a plumbing contracting business.
A plumbing company must satisfy separate contractor registration requirements and identify an appropriately licensed responsible Master Plumber.
This distinction matters for anyone planning to start a plumbing business rather than work only as an individual license holder.
Official license: Colorado Master Plumber.
State authority: Colorado State Plumbing Board, DORA.
Experience: 8,500 qualifying practical hours.
Testing provider: PSI.
Business operations: Separate Plumbing Contractor registration.
Review Colorado Plumbing Applications and Licensing Requirements before submitting your application.
Use the following steps to organize experience verification, state eligibility, PSI testing, and final licensing.
| Step | Requirement | What to Verify |
|---|---|---|
| Choose Master Plumber | Correct License Level | Confirm you need the statewide Master Plumber credential rather than Journeyworker or a local ICC license. |
| Verify Experience | 8,500 Hours | Document five full-time years of qualifying plumbing experience. |
| Collect Work Records | Employer Verification | Gather the required affidavits and practical experience documentation. |
| Review Training Credit | Eligible Plumbing Education | Ask the Board whether qualifying educational or apprenticeship credit applies. |
| Submit State Eligibility Application | DORA | Follow the approved initial licensing and examination application process. |
| Receive Approval | State Plumbing Board | Wait for examination eligibility and instructions from the Board. |
| Check Code Editions | IPC and IRC | Confirm whether your scheduled exam uses the 2021 or 2024 code cycle. |
| Schedule Through PSI | Testing Appointment | Register for the correct Colorado State Plumbing Board Master Plumber examination. |
| Prepare for 120 Questions | 270-Minute Exam | Complete timed practice and review all eleven exam categories. |
| Take the Exam | PSI Codebooks | Use the approved codebooks supplied by the testing center. |
| Complete License Issuance | DORA | Follow the Board's instructions after passing and complete any remaining application steps. |
| Register a Plumbing Business If Needed | Contractor Registration | Meet separate company requirements and designate the responsible Master Plumber. |
| Maintain Your License | Renewal and CE | Complete applicable continuing education and license renewal requirements. |
The Colorado State Plumbing Board uses PSI to administer the Master Plumber examination. The current published topic outline covers eleven plumbing subject areas.
| Exam Detail | Authority | Current Information |
|---|---|---|
| Official Exam | Colorado | Master Plumber |
| Licensing Authority | DORA | Colorado State Plumbing Board |
| Testing Provider | PSI | Computer-based examination |
| Scored Questions | PSI | 120 |
| Time Limit | PSI | 270 minutes |
| Additional Questions | PSI | Up to 10 unscored pretest questions |
| Additional Pretest Time | PSI | Up to 30 minutes |
| PSI Published Passing | PSI Bulletin | 70%, or 84 correct scored answers |
| DORA Application Passing Information | DORA | 75% has also been displayed; confirm current standard |
| Reference Format | PSI | Codebooks supplied at test center |
| IPC Edition in October 2026 | PSI Reference List | 2021 IPC |
| IRC Edition in October 2026 | PSI Reference List | 2021 IRC |
| Reported Code Transition | 2026 Exam Information | 2024 IPC and IRC from November 1, 2026; verify with PSI |
| Personal Books | PSI | Not permitted |
| Highlighting and Tabbing | PSI | Not permitted in testing-center references |
| Sanitary Drainage | PSI | 22 questions |
| Vents | PSI | 20 questions |
| Water Supply | PSI | 16 questions |
| Storm Drainage | PSI | 12 questions |
| Fixtures and Equipment | PSI | 10 questions |
| Isometric Analysis | PSI | 10 questions |
| Water Heaters | PSI | 8 questions |
| General Regulations | PSI | 6 questions |
| Traps, Interceptors, Separators | PSI | 6 questions |
| Indirect and Special Waste | PSI | 6 questions |
| Residential Fire Sprinklers | PSI | 4 questions |
| Experience Requirement | DORA | 8,500 hours, or five full-time years |
| License Renewal | DORA | Two-year licensing cycle |
| Continuing Education | DORA | Eight hours in each license year, subject to exemptions |
Official PSI exam outline: 120 scored questions in 270 minutes.
Highest-weight subjects: Sanitary Drainage, Vents, and Water Supply.
Codebooks: Supplied by PSI, without personal tabs or highlighting.
Passing-score discrepancy: Verify PSI's 70% listing against DORA's licensing instructions before your exam.
The official Colorado Master Plumber examination includes eleven scored plumbing subject categories. Understanding their weighting can help you plan your study time.
Sanitary Drainage Systems is the largest category with 22 questions. Review drainage fixture units, building drains, sewers, cleanouts, pipe slopes, sizing tables, and approved materials.
Vents follows with 20 questions. Study individual vents, common vents, wet vents, circuit venting, trap arms, vent sizes, developed lengths, and proper vent termination.
Water Supply contains 16 questions. Practice water distribution sizing, pressure requirements, fixture-unit calculations, backflow prevention, valves, and hot-water delivery.
These three subjects contain 58 of 120 scored questions, or approximately 48.3% of the examination.
Storm Drainage Systems contains 12 questions. Study roof drainage, storm piping, rainfall rates, secondary drainage systems, and scuppers.
Fixtures and Equipment contains ten questions. Review fixture clearances, plumbing connections, installation requirements, and equipment placement.
Isometric Analysis also contains ten questions. You may need to interpret a plumbing isometric, follow piping directions, identify vent arrangements, or determine fixture-unit loads.
Water Heaters contains eight questions. Review temperature and pressure protection, installation clearances, water heater connections, and safety requirements.
General Regulations contains six questions covering definitions, code administration, and broad plumbing requirements.
Traps, Interceptors, and Separators contains six questions. Understand trap installation, prohibited arrangements, interceptors, and special separation requirements.
Indirect and Special Waste Piping contains six questions. Study indirect waste connections, air gaps, and special plumbing discharge requirements.
Residential Fire Sprinklers contains four questions, completing the official outline.
Even experienced plumbers should not skip isometric practice. Plumbing drawings can look simple until you have to follow three pipe branches, two vent connections, and a drain that seems determined to hide behind the wall.
Use the correct plumbing code tables and practice applying the information rather than memorizing isolated numbers.
Begin by reading the current PSI Candidate Information Bulletin and checking the exact code editions for your exam date.
Next, organize your study schedule around the official 120-question subject outline. Focus heavily on drainage, venting, water supply, and isometric analysis.
Sanitary Drainage: Study drainage fixture units, slope, pipe sizing, cleanouts, building drains, and building sewers.
Venting: Review vent sizing, wet vents, trap arms, circuit vents, and vent terminals.
Water Distribution: Practice supply fixture-unit calculations, pressure, flow, hot-water piping, valves, and backflow prevention.
Storm Drainage: Learn roof drainage sizing, rainfall rates, horizontal conductors, and secondary drainage.
Isometric Drawings: Practice following drainage and vent piping in three dimensions.
Traps: Review trap seals, trap arms, interceptors, and permitted installations.
Fixtures: Study fixture spacing, minimum clearances, connections, and required equipment.
Water Heaters: Review installation, safety devices, temperature limits, and protection.
Plumbing Math: Practice sizing calculations, lengths, slopes, and unit conversions.
Code Navigation: Learn how to find answers in clean, unmarked IPC and IRC books.
Practice with a codebook that does not have personal tabs. California-style or other-state tabbing strategies are not appropriate for Colorado's current PSI testing-center reference rules.
Use the Colorado Master Plumber Online Exam Prep Course for structured review and exam-style questions.
Keep a notebook of missed questions while studying at home. During the actual exam, however, follow PSI's prohibition on outside notes and personal reference materials.
Understanding how water supply and drainage systems connect is a valuable master-level skill. Isometric analysis is part of the official Colorado exam, so practice recognizing pipe directions and connections.
Illustrative piping diagram for study only. Not a code-approved plumbing design.
Eight steps to organize your experience, state licensing application, examination, and possible business registration.
Confirm you need Colorado Master Plumber rather than Journeyworker, Residential, or a municipal ICC plumbing credential.
Prepare the required experience history and employer verification records.
Follow State Plumbing Board eligibility procedures and submit the required information.
Confirm the applicable IPC and IRC editions for your scheduled examination date.
Focus on drainage, venting, water supply, storm drainage, and isometric drawings.
Use timed 120-question study sessions and practice finding answers in clean reference books.
Use only the testing-center references and follow PSI identification and security requirements.
Complete DORA's licensing instructions and register a plumbing contractor business separately if applicable.
The current PSI content outline assigns the following scored question counts. The percentages are calculated from the 120-question total.
Total: 120 scored questions.
Top three subjects: Drainage, Vents, and Water Supply.
Combined: 58 questions, approximately 48.3% of the exam.
Top six subjects: 90 questions, or 75% of the scored exam.
Study advice: Prioritize high-weight subjects, but do not skip code navigation or plumbing math.
The official PSI bulletin lists the International Plumbing Code and International Residential Code as the supplied examination references.
These books are for preparation at home when purchased from Contractor Exam Preps. PSI supplies the approved testing copies at the exam center.
| Reference or Study Material | Edition | Purpose |
|---|---|---|
| International Plumbing Code | 2021 | Core plumbing code used in the October 2026 PSI exam reference list. |
| International Residential Code | 2021 | One- and two-family dwelling plumbing provisions used in the October 2026 reference list. |
| International Plumbing Code | 2024 | Prepare for the reported November 1, 2026 code transition if confirmed for your test date. |
| International Residential Code | 2024 | Residential plumbing code preparation for the reported future exam cycle. |
| Colorado Master Plumber Online Exam Prep Course | Contractor Exam Preps | Structured lessons, practice questions, test-taking methods, and subject review. |
| Colorado Journeyman Plumber Study Package | 2021 IPC | Supplementary plumbing code review and practice, not a substitute for master-level study. |
| Colorado Journeyman Ultimate Package | 2021 IPC | Additional IPC study, plumbing calculations, isometrics, and online learning. |
| ICC G27 Master Plumber with Gas Package | Municipal ICC Exam | Separate local ICC G27 preparation, not the statewide Colorado PSI Master Plumber examination. |
2021 exam references: IPC and IRC supplied at the test center.
2024 transition: Confirm the applicable codebooks with PSI before studying for a later examination date.
Personal materials: Highlighted books, tabs, handwritten notes, and personal reference books are not allowed in the PSI state exam.
Important distinction: Municipal ICC Master Plumber with Gas exams use different requirements from the Colorado State Plumbing Board examination.
The Colorado Master Plumber exam lets you consult code references provided by PSI. However, you cannot use your personal highlighted or tabbed books.
That means code navigation should be part of every study session.
Exam reference format: PSI-supplied IPC and IRC books.
Best practice: Use clean-book navigation drills at home.
Plumbing math: Memorize common formulas because PSI does not provide personal formula notes.
Testing time: The scored exam allows an average of 2.25 minutes per question.
A Colorado Master Plumber can perform plumbing work within the scope of the state's plumbing laws and licensing regulations.
Master plumbers have advanced responsibilities because plumbing systems affect health, sanitation, water quality, and building safety.
Work may involve installing, maintaining, and repairing water supply, drainage, waste, venting, fixtures, water heaters, valves, piping, and related plumbing systems.
Master plumbers often supervise plumbing installations and provide guidance to less experienced workers.
They also help ensure that work complies with code requirements and local inspection standards.
Advanced plumbing work may involve designing or reviewing piping arrangements, evaluating pipe sizes, calculating fixture demand, identifying potential cross-connections, and troubleshooting complex drainage issues.
Water supply and drainage must be designed as systems rather than unrelated pieces of pipe.
A drain with the wrong slope or a poorly sized vent can create problems throughout a building.
That is one reason Colorado tests sanitary drainage, venting, and water supply so heavily.
The Master Plumber license may also support the role of responsible individual for a registered plumbing contractor business.
However, an individual Master Plumber license does not eliminate the separate requirement for a company to register as a Plumbing Contractor when operating a plumbing contracting business.
Some cities and municipalities have additional registration, permit, or local contractor examination requirements.
For example, certain Colorado municipalities use ICC Master Plumber with Gas or related local examinations.
Those local credentials should not be confused with the statewide PSI examination.
Before starting work, confirm the applicable state licensing, local registration, permitting, and business requirements.
Individual credential: Colorado Master Plumber.
Work scope: Plumbing services and systems permitted under Colorado law.
Business registration: Separate Plumbing Contractor requirement.
Municipal exams: May differ from the statewide PSI Master Plumber exam.
| License or Exam | Authority | Main Requirement or Purpose |
|---|---|---|
| Residential Plumber | Colorado DORA | 3,400 qualifying hours; residential plumbing license. |
| Journeyworker Plumber | Colorado DORA | 6,800 qualifying hours; broader plumbing work qualification. |
| Master Plumber | Colorado DORA | 8,500 qualifying hours; highest individual plumbing license level. |
| Plumbing Contractor Registration | Colorado State Plumbing Board | Separate business registration with responsible Master Plumber. |
| Colorado Master PSI Exam | PSI | 120 scored questions; 270-minute scored-test time. |
| ICC G27 Master Plumber with Gas | ICC / Participating Municipalities | Separate local plumbing and fuel gas examination where accepted. |
| ICC G24 Master Plumber | ICC / Participating Agencies | National Standard plumbing examination, not automatically the Colorado state license examination. |
Colorado Master: 8,500 qualifying practical hours.
State examination: PSI, with 120 scored questions.
ICC municipal examinations: Check the specific city or licensing jurisdiction before purchasing a different exam package.
8,500 Practical Plumbing Hours
120 Scored Questions • PSI
DORA and Separate Contractor Registration
Experience verification: DORA requires employer-based documentation. Applicants should not verify their own work.
Exam passage: Does not guarantee a license without Board approval.
Contracting business: Requires additional registration and compliance requirements.
Use six weeks to practice the most heavily tested plumbing systems, code navigation, calculations, and full-length examinations.
The Colorado Master Plumber examination is challenging because it combines advanced plumbing knowledge with code interpretation, calculations, and piping diagram analysis.
Candidates must answer 120 scored questions within 270 minutes.
The most heavily tested subjects are sanitary drainage, vents, and water supply.
Those three categories alone account for 58 scored questions.
Questions may require determining a pipe size, identifying a venting rule, evaluating water distribution pressure, or following an isometric diagram.
Master-level questions can be more demanding than simple trade definitions.
For example, understanding what a vent does is useful. Choosing the correct vent arrangement for a complicated drainage layout requires more detailed knowledge.
Another challenge is the way Colorado administers its reference-assisted examination.
PSI supplies the approved codebooks at the test center.
You cannot use your own highlighted pages, installed reference tabs, or handwritten notes.
That means candidates should become comfortable finding information in clean IPC and IRC books.
Practice using the chapter structure, index, definitions, tables, and section numbers.
For calculations, work through the problem carefully before choosing an answer.
Pay attention to units, pipe sizes, fixture counts, slope, pressure, and developed length.
Study isometric diagrams regularly. They are easy to overlook and represent ten questions on the Master Plumber outline.
Complete full-length practice sessions. Then review mistakes using the correct codebook section.
The goal is not to memorize every page of the plumbing code. That would require an impressive memory and possibly a larger toolbox.
The better goal is to understand common rules, recognize which code section applies, and find the needed information without wasting time.
Arrival: PSI instructs candidates to arrive at least 30 minutes before the examination.
Identification: Bring current accepted photo identification matching the registration.
References: Supplied by PSI.
Results: PSI provides a score report after the exam.
Contractor Exam Preps offers a Colorado Master Plumber online preparation course and plumbing codebooks that support the knowledge tested in the PSI examination.
These products are designed for preparation before exam day. Personal printed books and tabs cannot be brought into the current Colorado State Plumbing Board examination.
Dedicated Colorado Master-Level Preparation
Core October 2026 Plumbing Reference
Residential Plumbing Code Reference
Supplementary Journeyworker Course: The Colorado Journeyman Plumber Ultimate Exam Prep Package offers additional IPC learning, isometrics, and plumbing math. Its target is the Journeyworker level rather than the Master examination.
Additional Practice Books: The Colorado Journeyman Plumber Exam Prep Package includes a 2021 IPC study approach and trade practice questions.
Municipal Option: The ICC G27 Master Plumber with Gas Exam Prep Package is intended for a different ICC examination used by participating local jurisdictions. It is not the Colorado statewide PSI Master Plumber test.
Before Ordering: Confirm the latest code editions, product availability, and course content for your specific exam date.
This custom credential-style illustration features Colorado's state outline, Rocky Mountain imagery, a pipe wrench, drainage and supply pipes, plumbing equipment, and water symbols.
It represents professional Master Plumber exam preparation. It is not an official license card or certificate from the Colorado State Plumbing Board.
• Colorado State Plumbing Board
• Department of Regulatory Agencies
• Master Plumber License
• PSI Examination
• 120 Scored Questions
• 270-Minute Scored Exam
• 8,500 Experience Hours
• International Plumbing Code
• International Residential Code
• Sanitary Drainage Systems
• Plumbing Vent Systems
• Water Supply and Distribution
• Storm Drainage
• Fixtures and Equipment
• Isometric Analysis
• Traps and Interceptors
• Water Heaters
• Backflow Prevention
• Plumbing Calculations
• Residential Fire Sprinklers
• Clean-Book Navigation
• Plumbing Contractor Registration
Prepare with current code materials, realistic practice questions, and a study routine based on the official PSI topic outline.
Colorado Master Plumber License Basics
The Colorado State Plumbing Board, part of DORA's Division of Professions and Occupations.
Yes. Master Plumber is the highest of Colorado's three main individual plumbing license levels.
DORA requires 8,500 qualifying practical plumbing hours, generally equivalent to five full-time years.
No. The Board requires proper experience verification from employers or other approved sources under its application rules.
Some approved training or education may qualify for limited credit. DORA evaluates the applicant's documentation under Board rules.
Colorado PSI Master Plumber Exam
PSI administers the examination for the Colorado State Plumbing Board.
The official examination outline contains 120 scored questions.
There are 270 minutes, or four hours and 30 minutes, for the scored examination.
PSI may include up to ten unscored pretest questions and provide up to 30 additional minutes for them.
The published PSI bulletin lists 70%, or 84 correct scored answers. DORA's application information has also shown 75%. Confirm the current controlling requirement with PSI and DORA before testing.
Follow DORA's application and eligibility process first. The Board provides instructions for approved applicants to schedule with PSI.
Codebooks and Exam References
It is reference-assisted. PSI supplies the approved IPC and IRC codebooks at the testing center.
No. The current PSI bulletin says the testing center provides the references and personal materials are not allowed.
You may use tabs for home study, but you cannot bring personal tabbed books or alter the codebooks supplied during the state examination.
The current detailed PSI reference list identifies the 2021 International Plumbing Code.
The PSI reference list identifies the 2021 International Residential Code.
Current 2026 examination information indicates a November 1, 2026 transition to the 2024 IPC and IRC. Confirm the exact edition and any transition options directly with PSI.
The PSI detailed reference list says the examination is based on the listed IPC and IRC editions rather than Colorado's separate state amendments.
PSI advises candidates to know common plumbing theory formulas. Do not expect to bring a personal formula sheet into the examination.
Master Plumber Exam Subjects
Sanitary Drainage Systems is largest with 22 scored questions.
Vents account for 20 scored questions.
Water Supply accounts for 16 scored questions.
Yes. Isometric Analysis includes ten scored questions.
Yes. Storm Drainage Systems account for 12 scored questions.
Yes. Water Heaters account for eight scored questions.
Yes. The Master Plumber examination includes four residential fire sprinkler questions.
Licensing and Plumbing Contractor Registration
No. The Master Plumber license is an individual credential, while plumbing contracting businesses must satisfy separate state registration requirements.
Yes, subject to Colorado's responsible-party and contractor registration requirements.
Yes. A local ICC G27 examination is not the same as the Colorado State Plumbing Board's PSI Master Plumber examination.
Active plumbers generally need eight approved continuing education hours in each license year of the two-year cycle, subject to first-renewal exceptions and Board rules.
DORA requires at least four code-related CE hours during the two-year license period.
Contractor Exam Preps Products
Yes. The store offers a Colorado Master Plumber Online Exam Prep Course for plumbing code review and practice questions.
Yes. Contractor Exam Preps lists the 2021 IPC for individual purchase.
Yes. Contractor Exam Preps sells the 2021 IRC for residential plumbing and related code study.
They may help review plumbing fundamentals and calculations, but they are not a replacement for the Colorado Master Plumber examination outline.
The ICC G27 package prepares candidates for a different Master Plumber with Gas examination. Confirm whether that separate exam is required by your municipality. It is not the statewide PSI Master Plumber test.
No. Study products do not guarantee passing the exam, state eligibility approval, or license issuance.
Watch this related 1 Exam Prep video introducing the International Plumbing Code and how candidates can understand its organization and major subjects.
The lesson discusses IPC editions including 2021 and 2024, making it useful background for Colorado Master Plumber candidates navigating the 2026 code transition.
This video is for code study. Your actual Colorado examination rules, reference editions, and score requirements are controlled by PSI and the State Plumbing Board.
Video: International Plumbing Code Overview, Course Preview.
Channel: 1 Exam Prep.
Related topics: IPC structure, code sections, code editions, navigation, and plumbing exam study.
Colorado reminder: PSI provides codebooks at the test center, and personal highlighted or tabbed copies are not permitted.
Watch 1 Exam Prep's International Plumbing Code Video on YouTube
Use Contractor Exam Preps for state-specific Master Plumber study, IPC and IRC books, plumbing calculations, and related code learning. Use Colorado DORA and PSI for official exam and licensing requirements.
Colorado Master Plumber: State individual license issued through DORA.
PSI Master exam: 120 scored questions, 270 minutes.
Exam references: Supplied IPC and IRC codebooks.
Code update: Confirm the October 2026 or November 2026 reference edition for your test date.
Business registration: Separate from the individual Master Plumber license.
Prepare for Colorado Master Plumber licensing with stronger knowledge of sanitary drainage, plumbing vents, water supply, storm drainage, fixtures, traps, interceptors, water heaters, and isometric drawings.
The PSI examination includes 120 scored questions with 270 minutes allowed for the scored portion.
PSI may include additional unscored questions with extra time, and candidates should confirm the current passing standard with the testing provider and the Colorado State Plumbing Board.
Sanitary Drainage, Vents, and Water Supply are the three largest categories. Together, they account for 58 scored questions.
Focus on the official outline, but do not overlook plumbing calculations, storm drainage, isometric analysis, fixture requirements, and water heater safety.
Study the applicable International Plumbing Code and International Residential Code editions for your scheduled exam.
Remember that PSI supplies the approved reference books at the testing center. Personal highlighted or tabbed books are not permitted.
Contractor Exam Preps offers a Colorado Master Plumber online preparation course and IPC and IRC reference books to help you prepare.
Build a study routine using plumbing code review, clean-book navigation, calculations, and timed practice questions.
Colorado also requires 8,500 qualifying hours of practical plumbing experience for the Master Plumber credential.
Applicants should document their work correctly and follow the State Plumbing Board's eligibility process.
If your goal includes owning or operating a plumbing company, review Colorado's separate Plumbing Contractor registration and responsible Master Plumber requirements.
The right study materials, a realistic schedule, and careful code reading can help turn years of plumbing experience into a focused exam preparation plan.
Find additional plumber licensing and contractor examination study materials at ContractorExamPreps.com.
