It’s wild to think about, but indoor plumbing has been around for nearly 6,000 years. Yet, despite that long history, the modern plumbing systems we use today have only become standard in the last century.
Because society relies on you to keep the clean water flowing and the wastewater going, you aren’t just a laborer—you’re a highly skilled technician. In Colorado, that skill translates into serious career growth and business opportunities, but there is one major hurdle standing between you and that pay raise: The State Board Exam.
To operate legally under the Colorado Department of Regulatory Agencies (DORA), you have to prove you know the code. At Exam Insiders, we know that being a great plumber doesn’t always mean you’re a great test-taker. That’s where we come in.
Here is the breakdown of which license is right for you, the materials you need to bring to the testing center, and how to pass the first time.
Which License Are You Targeting?
Colorado divides its plumbing licenses into three main tiers. Knowing the requirements for each is step one.
1. Residential Plumber
This is often the entry point for those focused on home building and renovation.
- The Job: You can install and repair plumbing in 1-4 family dwellings (maximum two stories above ground).
- The Prerequisites: You need two years (3,400 hours) of verifiable work experience.
- The Exam:
- Format: 100 questions.
- Time: 240 minutes (4 hours).
- Passing Score: 70% (70 correct answers).
- Insider Note: This exam covers the standard plumbing topics but adds specific questions on residential fire sprinklers and water heaters. Don’t skip those chapters in your study guide!
2. Journeyworker Plumber
Note: You may see this referred to as “Journeyman.”
This license opens the door to commercial work.
- The Job: You can work on commercial and residential systems under the supervision of a Master Plumber.
- The Prerequisites: Four years (6,800 hours) of relevant experience.
- The Exam:
- Format: 100 questions.
- Time: 240 minutes (4 hours).
- Passing Score: 70% (70 correct answers).
- Key Topics: Water supply, vents, fixtures, piping support, sanitary/storm drainage, and indirect waste piping.
3. Master Plumber
The top tier. This is for those ready to run the show.
- The Job: You can supervise other plumbers and run your own plumbing contracting business.
- The Prerequisites:Five years (8,500 hours) of experience.
- Crucial Detail: If you are currently a Journeyworker, you must hold that license for at least one full year before applying for Master.
- The Exam:
- Format: 120 questions.
- Time: 270 minutes (4.5 hours).
- Passing Score: 70% (84 correct answers).
- The Strategy: This test covers the same topics as the Journeyworker exam but expects a deeper understanding of code applications and sizing calculations. Speed is essential here.
The Gear: Permitted Books and Materials
Here is the most important thing to remember: These exams are Open Book.
However, “Open Book” doesn’t mean “Easy.” If you don’t know where to look, you will run out of time flipping pages. To pass, you must arrive at the testing center with the specific code books adopted by the Colorado Plumbing Board.
You need these books in your hand:
- 2021 International Plumbing Code (IPC): This is your bible for the Journeyworker and Master exams.
- 2021 International Residential Code (IRC): Mandatory for the Residential exam.
- Colorado Plumbing Code Amendments: Colorado tweaks the international codes. You must have a printed copy of the current state amendments.
The Exam Insiders Strategy:
You cannot write in your books during the test, but you can use permanent tabs. We highly recommend buying a pre-tabbed book or a tab set. Being able to flip instantly to “Venting” or “Water Supply” will save you 10–15 minutes of panic during the exam.
FAQ: Common Questions from Our Students
Q: Can I just highlight my book, or can I write notes in the margins?
A: You can highlight and underline text, but do not write notes, formulas, or cheat sheets in the margins. The proctors check your books. If they find writing, they may confiscate your materials or disqualify you.
Q: I have a license in another state. Do I still have to test?
A: Maybe not. Colorado has endorsement agreements with specific states. You will need to submit a “License Verification” to DORA. If your current state’s standards match Colorado’s, you might get a pass. If not, you’re taking the exam.
Q: What happens if I fail?
A: Don’t panic. It happens. You will receive a score report showing your weak areas. You can reschedule the exam through PSI, though you will have to pay the exam fee again. Our goal is to make sure you pass on attempt #1.
Pass with Confidence
The difference between a “Fail” and a “Pass” usually isn’t plumbing knowledge—it’s test-taking strategy. You need to know how to navigate the IPC/IRC quickly, how to interpret the phrasing of tricky questions, and how to manage your time.
At Exam Insiders, we don’t just teach you plumbing; we teach you how to beat the exam. Our courses feature:
- 24/7 Online Access: Study on your schedule, not ours.
- Practice Exams: Simulations that mimic the real test environment.
- Expert Support: Content developed by industry pros who have been where you are.
Ready to get licensed and boost your earning potential?
Contact Exam Insiders today to grab your books, tabs, and prep courses. Let’s get you certified.