Master Plumber Exam Prep
Start with 20 free, original master plumber practice questions, then check your exam's format and follow the 8-week study plan below. Master plumber exams are set by your state or local licensing authority, so match your code book and edition to your own candidate bulletin.
Practice questions
Original, unofficial practice
Original, unofficial practice. These are not actual exam questions or a full-length mock exam. The sizing drills give you the data you need, and the study path tells you where the matching rule lives in your own code book. Start with MP-01, then reveal the explanation.
MP-01 · Plumbing math: grade and fall
A building sewer is 125 feet long and must be laid at a 2% grade. What is the total fall?
Reveal answer and explanation
Answer: A. 30 inches
2% means 2 feet of fall for every 100 feet of pipe. 125 × 0.02 = 2.5 feet, and 2.5 × 12 = 30 inches.
Why the others miss: B treats 2% as ¼ inch per foot (125 × 0.25 = 31.25). They're close, but ¼ inch per foot is about 2.08%, not 2%. C stops at 2.5 and forgets that's feet. D uses ⅛ inch per foot.
Study path: Converting percent grade to inches per foot and back; the minimum-slope table in your code's sanitary drainage chapter.
Source: Calculation from the stated inputs.
MP-02 · Plumbing math: grade and fall
A 72-foot building drain is installed at ⅛ inch per foot. How much lower is the downstream end than the upstream end?
Reveal answer and explanation
Answer: B. 9 inches
72 × ⅛ = 9 inches.
Why the others miss: A uses 1/16 inch per foot. C uses ¼ inch per foot. D assumes one inch of fall per 6 feet, which isn't in the question.
Study path: Slope requirements by pipe size in your code's drainage chapter.
Source: Calculation from the stated inputs.
MP-03 · Plumbing math: volume
A pipe with a 4-inch inside diameter is 100 feet long and full of water. Using 231 cubic inches per gallon, about how many gallons does it hold?
Reveal answer and explanation
Answer: A. 65.3 gallons
Area = π × radius² = 3.1416 × 2² = 12.57 square inches. Length = 100 × 12 = 1,200 inches. Volume = 12.57 × 1,200 = 15,080 cubic inches, and 15,080 ÷ 231 = 65.3 gallons. Check it in feet: π × (1/6 ft)² × 100 ft = 8.73 cubic feet, × 7.48 = 65.3 gallons.
Why the others miss: B uses the diameter (4) as the radius. C is the right volume in cubic feet, not gallons. D mixes the two area formulas and divides by 4 an extra time (π × d² ÷ 4 is the same thing as π × r², so never apply both).
Study path: Cylinder volume and unit conversions: cubic inches, cubic feet, gallons.
Source: Calculation; 231 cubic inches per gallon and 7.48 gallons per cubic foot are standard conversions.
MP-04 · Plumbing math: pressure and elevation
Static pressure at the water main is 80 psi. A fixture outlet is 46 feet above the main. Using 0.433 psi per foot of elevation and ignoring friction loss, what is the static pressure at the outlet?
Reveal answer and explanation
Answer: A. 60.1 psi
Lifting water 46 feet costs 46 × 0.433 = 19.9 psi. 80 − 19.9 = 60.1 psi left at the outlet.
Why the others miss: B adds the elevation loss instead of subtracting it. C subtracts feet straight from psi. D is the loss itself, not the pressure that's left.
Study path: Head and pressure (1 psi lifts water 2.31 feet). On a real sizing problem you then subtract friction and meter losses and compare with the minimum pressure your code requires at the fixture.
Source: Calculation; 0.433 psi per foot of water is the standard water-column conversion.
MP-05 · Plumbing math: offsets
A 45° offset has to move a line over 30 inches. What is the travel, the center-to-center length of the diagonal piece?
Reveal answer and explanation
Answer: B. 42.4 inches
For a 45° offset, travel = offset × 1.414. 30 × 1.414 = 42.4 inches.
Why the others miss: A divides by 1.414 instead of multiplying. C uses 2.000, the multiplier for a 30° offset. D uses 1.155, the multiplier for a 60° offset.
Study path: Offset constants (45° = 1.414, 60° = 1.155, 30° = 2.000). Subtracting fitting takeoff to get a cut length is a separate step.
Source: Geometry: travel = offset ÷ sine of the fitting angle.
MP-06 · Sanitary drainage: fixture units
Use these supplied drainage fixture unit (DFU) values: water closet 4, lavatory 1, bathtub 2, kitchen sink 2, dishwasher 2, clothes washer 2. A house has 2 water closets, 3 lavatories, 2 bathtubs, 1 kitchen sink, 1 dishwasher, and 1 clothes washer. What is the total DFU load?
Reveal answer and explanation
Answer: C. 21
(2 × 4) + (3 × 1) + (2 × 2) + 2 + 2 + 2 = 8 + 3 + 4 + 6 = 21 DFU.
Why the others miss: A counts fixtures, not fixture units. B rates each water closet at 2. D rates each water closet at 6.
Study path: Your code's drainage fixture unit table. Check whether it has a bathroom-group row and when that row applies instead of separate fixtures.
Source: Arithmetic from the supplied values. These are exercise values, not a quoted code table.
MP-07 · Sanitary drainage: sizing from a table
A building drain at ¼ inch per foot carries 45 DFU. Use this supplied table of maximum DFU at that slope: 2½-inch, 24; 3-inch, 42; 4-inch, 216; 5-inch, 480. What is the minimum drain size?
Reveal answer and explanation
Answer: C. 4 inches
45 is more than the 3-inch limit of 42, so move up to the next size whose limit is at least 45. That's 4-inch (216).
Why the others miss: B is the classic miss. 45 is close to 42, but a table maximum is a ceiling, not a target. A is far too small. D works but isn't the minimum.
Study path: The building drain and sewer sizing table in your code, its slope columns, and its footnotes, including any minimum-size rules.
Source: Arithmetic from the supplied table. These are exercise values, not a quoted code table.
MP-08 · Sanitary drainage: stacks and risers
A three-story stack receives a 21-DFU branch on each floor. What DFU load does the stack carry at its base?
Reveal answer and explanation
Answer: C. 63
Loads add up as you go downstream: 21 + 21 + 21 = 63 DFU at the base.
Why the others miss: A counts one floor. B stops above the lowest branch. D adds a fourth floor that isn't there.
Study path: Stack sizing in your code: the total on the stack and any per-branch-interval limits. Riser and isometric questions test this running total constantly.
Source: Arithmetic from the stated inputs.
MP-09 · Sanitary drainage: continuous flow
A sump pump discharges a continuous 15 gpm into the drainage system. Using a supplied conversion of 2 DFU per gpm of continuous flow, how much load does it add?
Reveal answer and explanation
Answer: C. 30 DFU
15 gpm × 2 DFU per gpm = 30 DFU.
Why the others miss: A divides instead of multiplying. B treats gpm as DFU. D applies the factor twice.
Study path: The continuous or semicontinuous flow provision in your code's fixture-unit section.
Source: Arithmetic from the supplied conversion (exercise value).
MP-10 · Storm drainage: roof runoff
A roof has 6,000 square feet of horizontal projected area. The design rainfall rate is 3 inches per hour. Using 0.0104 gpm per square foot for each inch per hour of rain, what is the design runoff?
Reveal answer and explanation
Answer: B. 187.2 gpm
6,000 × 3 × 0.0104 = 187.2 gpm. Where the constant comes from: 1 inch of rain on 1 square foot is 1/12 cubic foot, or about 0.623 gallon. Spread over 60 minutes, that's 0.0104 gpm.
Why the others miss: A leaves out the 3-inch rainfall rate. C slips a decimal. D multiplies area by rainfall and stops, which isn't a flow at all.
Study path: Storm drainage sizing: where your code gets its rainfall rate, how its leader and drain tables are set up, and how it treats horizontal projected area and any adjacent wall area.
Source: Calculation; the constant is derived in the explanation.
MP-11 · Water supply: flow and velocity
Water flows at 8 feet per second through a pipe with a 1-inch inside diameter. Using gpm = 2.448 × velocity (ft/s) × inside diameter² (inches), what is the flow?
Reveal answer and explanation
Answer: C. 19.6 gpm
2.448 × 8 × 1² = 19.6 gpm.
Why the others miss: A divides the answer by 4. B treats feet per second as gallons per minute. D plugs in 2 inches instead of the 1-inch diameter, and 2² = 4 makes it four times too big.
Study path: Your code's water-supply sizing method and any velocity limits. The formula shows why more demand at the same velocity needs a bigger pipe.
Source: 2.448 = 7.48 gal/ft³ × 60 s/min × π ÷ 4 ÷ 144 in²/ft² (derived).
MP-12 · Fuel gas: appliance load
A gas branch serves a 40,000 Btu/h water heater and a 65,000 Btu/h range. Using 1,000 Btu per cubic foot of natural gas, what flow must the branch carry?
Reveal answer and explanation
Answer: C. 105 cfh
(40,000 + 65,000) ÷ 1,000 = 105 cubic feet per hour.
Why the others miss: A and B size for one appliance. D forgets to convert Btu per hour into cubic feet per hour.
Study path: The pipe-sizing section of your fuel gas code. Use the heating value your exam supplies or your code specifies.
Source: Arithmetic from the supplied values.
MP-13 · Fuel gas: longest length method
For this drill, size gas pipe using the column equal to the longest run, or the next longer column if that length isn't listed. The run from the meter to the most remote outlet is 64 feet. The supplied capacity table has columns for 50, 60, 70, and 80 feet. Which column do you use?
Reveal answer and explanation
Answer: C. 70 ft
64 feet isn't listed, so go to the next longer column: 70 feet. Going down would credit the pipe with more capacity than a 64-foot run really has.
Why the others miss: A and B round down, which overstates capacity. D skips past the next longer column.
Study path: The pipe-sizing methods in your fuel gas code. Know which method your exam expects and where its capacity tables are.
Source: Method as stated in the stem (exercise premise).
MP-14 · Fuel gas: sizing from a table
Continuing MP-12 and MP-13, the branch carries 105 cfh. Supplied capacities in the 70-foot column are: ½-inch, 64 cfh; ¾-inch, 134 cfh; 1-inch, 274 cfh; 1¼-inch, 563 cfh. What is the minimum pipe size?
Reveal answer and explanation
Answer: B. ¾ inch
105 cfh is more than ½-inch can carry (64) but within ¾-inch capacity (134).
Why the others miss: A is undersized. C and D would work but aren't the minimum.
Study path: Size each section for the total load it carries, working from the outlets back to the meter.
Source: Arithmetic from the supplied table. These are exercise values, not a quoted code table.
MP-15 · Fuel gas: pressure units
An appliance's manifold pressure is listed as 7 inches of water column. Using 27.7 inches of water column per psi, what is that in psi?
Reveal answer and explanation
Answer: B. 0.25 psi
7 ÷ 27.7 = 0.253 psi.
Why the others miss: A and C misplace the decimal. D multiplies instead of dividing.
Study path: Gas pressure units and the pressure ranges your fuel gas code treats differently.
Source: Calculation; 27.7 inches of water column per psi is the standard conversion.
MP-16 · Fuel gas: combustion air
A room holds gas appliances totaling 115,000 Btu/h. For this drill, combustion air comes from an adjoining indoor space through two openings, and each opening must have at least 1 square inch of free area per 1,000 Btu/h of total input. What is the minimum free area of each opening?
Reveal answer and explanation
Answer: C. 115 sq in
115,000 ÷ 1,000 = 115 square inches, and the rule applies to each opening, not to the two combined.
Why the others miss: B splits the area between the two openings. A divides by 4,000 instead of 1,000. D doubles the answer.
Study path: Combustion, ventilation, and dilution air in your fuel gas code. Several methods exist (indoor air, outdoor air, ducted), and the ratio depends on the method, so identify the method before you use a number.
Source: Arithmetic from the rule stated in the stem (exercise premise).
MP-17 · Plumbing math: volume
A rectangular tank is 6 feet long and 4 feet wide, with water 5 feet deep. Using 7.48 gallons per cubic foot, how many gallons does it hold?
Reveal answer and explanation
Answer: C. 897.6 gallons
6 × 4 × 5 = 120 cubic feet. 120 × 7.48 = 897.6 gallons.
Why the others miss: A divides by 7.48 instead of multiplying. B stops at cubic feet. D uses a 6-foot water depth.
Study path: Rectangular and cylindrical volume, which shows up in sump, interceptor, and storage questions.
Source: Calculation.
MP-18 · Safety: OSHA scaffolds
Under federal OSHA construction rules, each scaffold and scaffold component must support, without failure, its own weight and at least how many times the maximum intended load?
Reveal answer and explanation
Answer: B. 4 times
29 CFR 1926.451(a)(1) requires each scaffold and component to support its own weight plus at least 4 times the maximum intended load.
Why the others miss: A is too low. C and D overstate this general rule. Other paragraphs of the scaffold standard cover specific parts, so read the paragraph a question points to.
Study path: 29 CFR 1926 Subpart L (Scaffolds).
Source: 29 CFR 1926.451(a)(1)
MP-19 · Safety: OSHA trench egress
A sewer trench is 4½ feet deep. Under federal OSHA rules, a stairway, ladder, ramp, or other safe way out must be placed so workers travel no more than how far sideways to reach it?
Reveal answer and explanation
Answer: B. 25 feet
Trenches 4 feet deep or more need a safe way out within 25 feet of lateral travel [29 CFR 1926.651(c)(2)].
Why the others miss: D mixes up two numbers: 4 feet triggers the way-out rule, while 5 feet is the cave-in protection threshold in MP-20. A and C aren't the rule.
Study path: 29 CFR 1926 Subpart P (Excavations).
Source: 29 CFR 1926.651(c)(2)
MP-20 · Safety: OSHA cave-in protection
An excavation is 4 feet deep in soil, not stable rock. A competent person examines the ground and finds no sign of a potential cave-in. Under 29 CFR 1926.652(a)(1), is a protective system (sloping, shoring, or shielding) required?
Reveal answer and explanation
Answer: B. No. It's under 5 feet deep and the competent person found no sign of a cave-in.
Protection is required unless the excavation is entirely in stable rock, or it's less than 5 feet deep and a competent person's examination shows no indication of a potential cave-in. This excavation meets the second exception.
Why the others miss: A ignores the exceptions. C invents a depth that isn't in this rule. D borrows the 25-foot distance from the way-out rule in MP-19.
Study path: 29 CFR 1926.651 and 1926.652.
Source: 29 CFR 1926.652(a)(1)
How to use your misses
Sort your misses by domain, then start with the matching week of the study plan. Count a lucky guess as a miss. Twenty questions can't measure your readiness for an exam of 80 to 308 questions, so treat your score here as a pointer to what to study next, not a prediction.
One more thing: these drills hand you the table values. Many exams expect you to find them in the code book instead. In Weeks 3 to 6 of the plan, redo each sizing drill using the real table in your own book.
Check your exam before you study
There's no national master plumber exam. Your state or local licensing authority picks the test, the code book, the edition, and the rules for the book. Five things change how you should study, and your candidate bulletin answers all of them:
- Which code, and which edition? Most of the exams below use the International Plumbing Code (IPC). Texas lets you prepare with either the IPC and International Fuel Gas Code (IFGC) or the Uniform Plumbing Code (UPC). Editions differ too: Maryland lists 2018, Virginia 2021, and Colorado moves from 2021 to 2024 on November 1, 2026.
- Your book or theirs? Colorado hands you the IPC and IRC at the test center. Virginia, Maryland, and Michigan have you bring your own.
- Tabs, highlighting, notes? Virginia and Maryland allow highlighting and permanent tabs but no writing. Michigan allows chapter tabs only and no highlighting or marking of any kind. Colorado allows no marking at all.
- What else is on it? Fuel gas is 40 of Maryland's 100 questions. Virginia builds 10 regulation questions into its exam. Maryland's reference list includes a plumbing math text and OSHA's construction rules. Colorado tests isometric drawings.
- Calculator and passing score. Colorado gives you an online calculator; Maryland lists handheld calculators as prohibited items. Most exams below pass at 70%, but Michigan requires 75%.
IPC or UPC? They're separate model codes, written by the International Code Council and IAPMO. Section numbers and some sizing values differ. Study the one your exam names. If your exam lets you pick (Texas), choose one and stick with it.
Before you buy, tab, or memorize anything, check that its code family and edition match your bulletin. A thousand practice questions on the wrong edition train the wrong answers.
Your exam card
Fill this in from your bulletin and approval notice. It's your own record, not an eligibility decision.
| Record | Your exam |
|---|---|
| Licensing authority | ____________________ |
| Exact exam name or ID | ____________________ |
| Testing vendor | ____________________ |
| Test date and time | ____________________ |
| Code book(s) and edition for that date | ____________________ |
| State or local amendments tested? | ____________________ |
| Bulletin title, revision date, and link | ____________________ |
| Questions, time, passing score | ____________________ |
| Official subject categories and counts | ____________________ |
| Books provided or brought | ____________________ |
| Tab, highlight, and note rules | ____________________ |
| Calculator rule | ____________________ |
| Retake waiting period | ____________________ |
| ID, arrival, and approved accommodations | ____________________ |
Six master plumber exams side by side
These come from current official bulletins. They're examples, not a complete list, and they show how much exams differ. Use your own bulletin for your test date.
| Exam (authority / test vendor) | Questions | Time | To pass | Code basis | Books |
|---|---|---|---|---|---|
| Colorado (State Plumbing Board / PSI) | 120 scored, plus up to 10 unscored | 270 min, plus 30 min for unscored items | 70% (84 correct) | 2021 IPC and 2021 IRC; 2024 IPC and IRC starting Nov. 1, 2026 | Provided at the test center; no writing, highlighting, or indexing |
| Virginia (DPOR Board for Contractors / PSI) | 80 (journeyman and master take the same portion) | 210 min | Passing score of 60 | 2021 IPC and Virginia tradesman regulations | Bring your own; highlight or index beforehand; permanent tabs only |
| Maryland (Board of Plumbing / PSI; Master Plumber/Gas Fitter) | 100 | 240 min | 70% | 2018 IPC, 2018 IFGC, a plumbing math text, a backflow text, OSHA 29 CFR 1926 | Bring your own; highlight or underline; approved permanent tabs; no writing |
| Michigan (LARA Bureau of Construction Codes / PSI) | 130 | 180 min | 75% | 2021 Plumbing Code book, plus two state acts shown on screen | Bring your own; chapter tabs only; no highlighting or marking |
| Texas (TSBPE / Pearson VUE) | 308, written only | 360 min, plus a 30-min break | 70% | Texas plumbing law and rules, plus 2018 IPC and IFGC or 2018 UPC | Check the TSBPE candidate handbook |
| ICC G24 National Standard Master Plumber (used by some local jurisdictions / Pearson VUE) | 100 | 4 hours | 70% | 2018 IPC | Open book |
Sources: Colorado PSI bulletin, updated Sept. 3, 2026, pp. 5–8 · Virginia PSI bulletin, July 23, 2026, pp. 2–5 · Maryland PSI bulletin, Aug. 10, 2026, pp. 5–7 · Michigan PSI bulletin, effective Apr. 29, 2026 · Pearson VUE TSBPE Candidate Handbook, Aug. 2025, pp. 9–12 · ICC National Contractor/Trades Examination Information Bulletin, June 30, 2026, pp. 11, 23 and ICC: what is a passing score?
Colorado's code change. PSI says the Colorado plumbing exams move to the 2024 IPC and IRC on November 1, 2026. The same bulletin says the 2021 books will remain available on request until February 1, 2027. That second sentence does not change the stated exam-update date, so if your appointment falls near the transition, confirm which reference books PSI will provide for your session. (Colorado PSI bulletin, p. 6)
Texas code update pending. TSBPE proposed moving to the 2021 codes in July 2026 (Texas Register, Aug. 14, 2026). Until TSBPE announces a change, its Pearson VUE handbook lists the 2018 editions. Check TSBPE before you buy books.
ICC's passing score is 70%, not 75%. ICC's own help page says contractor and trade exams need 70%; the scaled 75 applies to its certification exams, such as plumbing inspector.
Pace yourself
Average time per question = minutes allowed ÷ questions delivered. From the table:
- Texas: 360 ÷ 308 = about 1.2 minutes
- Michigan: 180 ÷ 130 = about 1.4 minutes
- Colorado: 300 ÷ 130 (if all 10 unscored items appear) = about 2.3 minutes
- Maryland and ICC G24: 240 ÷ 100 = 2.4 minutes
- Virginia: 210 ÷ 80 = about 2.6 minutes
These are averages, not limits per question. On the faster exams, speed in the code book matters as much as knowing the answer.
What the outlines tell you to prioritize
Official outlines show where the questions go. They show coverage, not difficulty or how many hours a topic needs.
| Topic | Colorado (120) | Virginia (80) | Maryland (100) | ICC G24 |
|---|---|---|---|---|
| Sanitary drainage and venting | 22 drainage + 20 vents | 24 drainage, waste, and vent | 13 drainage, waste, and vent | 11% drainage + 8% vents |
| Water supply | 16 | 10 | 8 | 11% |
| Backflow prevention | Not listed separately | 10 | 10 | Not listed separately |
| Storm drainage | 12 | 10 | Not listed separately | 2% |
| Fuel gas | Not listed separately | Not listed separately | 40 | Not listed separately |
| Isometric analysis | 10 | Not listed separately | Not listed separately | Not listed separately |
| Plumbing math | Not listed separately | Not listed separately | 7 | Not listed separately |
| Administration, general regulations, law | 6 general regulations | 5 general regulations + 10 Virginia regulation | 5 fundamentals and safety | 46% administration and general regulations |
"Not listed separately" means it isn't its own category on that outline, not that it can't show up inside another one. Sources: Colorado, p. 8 · Virginia, p. 5 · Maryland, p. 7 · ICC bulletin.
Three patterns stand out. Drainage and venting are heavy on every outline. Maryland is close to half fuel gas, so a plumbing-only plan would leave a big gap there. And ICC's G24 puts nearly half its weight on administration and general regulations, so the early chapters of the IPC deserve real time.
Set your own priorities. Copy your bulletin's categories into this table and rate yourself honestly.
| Official category | Official count or weight | My confidence (1–5) | Priority |
|---|---|---|---|
| Worksheet entry 1 | |||
| Worksheet entry 2 | |||
| Worksheet entry 3 | |||
| Worksheet entry 4 |
- Big category, low confidence: study first.
- Big category, high confidence: keep it sharp with timed questions.
- Small category, low confidence: targeted cleanup later.
- Not on your outline: don't let generic prep material pull you into it.
How to study for an open-book plumbing exam
Open book doesn't mean less preparation. It changes the skill from memorizing every rule to recognizing the problem, picking the right book, and finding the controlling section or table fast.
Use the same lookup path every time:
key word → index → chapter and section → exceptions and footnotes → answer
The step people skip is the last one before the answer. A table value with a footnote or exception attached can make a confident answer wrong.
- Learn the layout first. Know where the definitions, general regulations, fixtures, water supply, drainage, vents, traps, and storm chapters sit, and where each chapter's tables are.
- Mark only what your bulletin allows. Rules range from "highlight and tab" (Virginia, Maryland) to "chapter tabs only" (Michigan) to "no marking at all" (Colorado). If the book is provided, practice in a clean book.
- Practice finding answers, not reading them. Time your lookups and log the search term you tried first. Slow lookups are as fixable as wrong answers.
Code-navigation drill
Do these in your own exam book, with a timer set to your exam's average pace from the list above. Your book is the answer key, because the section numbers depend on your code and edition. Record each lookup:
| Drill | Find this | Search term you tried first | Section or table | Time | Right path the first time? |
|---|---|---|---|---|---|
| N-01 | The definition of "developed length" | ||||
| N-02 | The minimum slope for a 3-inch horizontal drain | ||||
| N-03 | The fixture-unit value for a bathroom group | ||||
| N-04 | The table for sizing building drains and sewers | ||||
| N-05 | The water pressure above which a pressure-reducing valve is required | ||||
| N-06 | The minimum and maximum trap seal depth | ||||
| N-07 | The rules for a water heater relief valve's discharge pipe | ||||
| N-08 | The rainfall rate your exam uses, or where the code says to get it | ||||
| N-09 | How to vent an island fixture | ||||
| N-10 | Who interprets the code and approves alternative materials |
Repeat the drill a week later. If a lookup is still slow, that section is a candidate for a permitted tab or more practice.
Your 8-week study plan
Plan on five 75-minute sessions a week, about 6¼ hours weekly and 50 hours over eight weeks. This is an editorial schedule, not an official requirement or a guarantee. Shift time toward your own outline's biggest categories.
Every session: 10 minutes recalling last session's rules from memory, 50 minutes on the week's task, and 15 minutes fixing and logging mistakes.
| Week | Focus | Do this | Done when you have |
|---|---|---|---|
| 1 | Match your exam | Fill in the exam card from your bulletin; get the right books and edition; mark them within the rules. Take MP-01 to MP-20 cold. | A complete exam card and a list of missed domains |
| 2 | Code navigation | Learn the layout of every permitted book. Run the code-navigation drill twice, the second time timed. | A lookup log with a section or table for every drill |
| 3 | Sanitary drainage | Fixture units, building drain and stack sizing, slope. Rework MP-06 to MP-09 using your own code's tables. | Three drains sized from a fixture list without notes |
| 4 | Venting and traps | Vent sizing, developed length, trap seals, interceptors; trace the vents on an isometric drawing. | A vent-sizing worksheet and a one-page trap and interceptor rule sheet |
| 5 | Water supply and backflow | Pressure, demand, velocity, pipe sizing, backflow devices. Rework MP-04 and MP-11. | A water supply sized from the meter to the farthest fixture |
| 6 | Fuel gas and storm drainage | Gas loads, the longest length method, combustion air, roof area and leader sizing. Rework MP-10 and MP-12 to MP-16. | One gas system and one roof sized start to finish |
| 7 | Your exam's extras | Whatever your outline lists: water heaters, isometrics, fire sprinklers, accessibility, OSHA, state law. Rework MP-18 to MP-20 if OSHA is on your list. | A gap list with one source section for each gap |
| 8 | Timed rehearsal | Two timed half-sets at your exam's pace with your permitted books, each followed by a review. Check logistics. | A short repair list and your exam-day checklist |
The five sessions in each week
Week 1: Match your exam
- Fill in the exam card from your bulletin and approval notice.
- Get the code book or books and edition your bulletin names; add only the marks it allows.
- Answer MP-01 to MP-10 before opening any explanation. Mark guesses.
- Answer MP-11 to MP-20 the same way.
- Read every explanation, group misses by domain, and fill in the priority table above.
Week 2: Code navigation
- Read the table of contents of each permitted book and note where every chapter's tables are.
- Read the definitions chapter; find five terms from questions you missed.
- Run the code-navigation drill untimed.
- Run it again at your exam's pace.
- Re-find every slow lookup and write down a better search term.
Week 3: Sanitary drainage
- Find your code's fixture-unit table and rework MP-06 with its real values.
- Rework MP-07 with your code's building drain table and footnotes.
- Rework MP-08 and MP-09; trace a stack's running total on a riser drawing.
- Size a drain from a fixture list you write yourself.
- Redo the week's misses from a blank page.
Week 4: Venting and traps
- Read your code's vent chapter: vent types, sizing, and connection rules.
- Size the vents for a small group of fixtures and compute developed length.
- Read the trap and interceptor chapter; write a one-page rule sheet.
- Trace every vent on an isometric drawing and check each against the code.
- Redo the week's misses.
Week 5: Water supply and backflow
- Rework MP-04 and MP-11; list every pressure loss in a real sizing problem.
- Read your code's water-supply sizing method from start to finish.
- Size a supply from the meter to the farthest fixture.
- Read the backflow section; match each hazard to an acceptable device.
- Redo the week's misses.
Week 6: Fuel gas and storm drainage
- Rework MP-12 to MP-15 with your fuel gas code's real capacity tables.
- Read the combustion-air section; rework MP-16 using the method your code gives.
- Size a small gas system from the meter to every appliance.
- Rework MP-10 with your code's rainfall source and storm tables.
- Size the drains and leaders for a roof.
Week 7: Your exam's extras
- List every outline category you haven't touched yet.
- Study the biggest one.
- Study the next one, including any state law or regulations your bulletin names.
- If OSHA is on your list, read the subparts it cites and rework MP-18 to MP-20.
- Write one rule, condition, and source for each remaining gap.
Week 8: Timed rehearsal
- Rework MP-01 to MP-10 against the clock at your exam's pace, books in hand.
- Review them by method, including correct guesses.
- Rework MP-11 to MP-20 the same way.
- Review, then rerun your two slowest navigation drills.
- Go through the last-48-hours checklist below.
Short on time? For a 4-week version, combine Weeks 2 and 3, 4 and 5, and 6 and 7, and keep Week 8. Keep Week 1 too; matching your exam is the step you can't skip. With six weeks or more, spread your weakest outline categories over the extra weeks and repeat the navigation drill.
Retaking? Start from the weak areas on your score report. Check the waiting period first: Texas requires 30, 60, then 90 days after successive failures (TSBPE application, p. 1); ICC requires 10 days (ICC bulletin, p. 4); Colorado and Virginia may let you retest within about two days, if seats allow (Colorado, p. 4; Virginia, p. 14). Practice with fresh questions; don't try to rebuild or trade remembered exam questions.
Keep an error log
One row per mistake. The point is the next action, not the count.
| Question or task | Topic and code edition | Error type | Correct method and source | Next action |
|---|---|---|---|---|
| MP-07 | Building drain sizing (supplied table) | Went over a table maximum | 45 DFU is over the 3-inch limit of 42, so the answer is 4-inch | Redo MP-07 with your own code's table and two new loads near a limit |
| Your next miss |
Error types: wrong edition · wrong table or column · missed footnote or exception · units · arithmetic · misread the question · guessed.
The last 48 hours
- ☐ Reread your current bulletin; make sure nothing changed.
- ☐ Confirm your date, time, test center address, and arrival time.
- ☐ Confirm which ID you need.
- ☐ Confirm the calculator rule.
- ☐ Confirm every permitted book and its edition.
- ☐ Remove any tabs, notes, or loose pages your rules don't allow.
- ☐ Run 10 final lookups and 4 final calculation setups.
- ☐ Read your error log one last time.
- ☐ Stop adding new prep material. Rehearse what you already studied.
Quick answers
Is the master plumber exam open book? Usually, but on different terms. Virginia, Maryland, and Michigan have you bring your own books under their marking rules. Colorado provides the books and bans marking them. ICC's G24 is open book.
What's the passing score? 70% on the Colorado, Maryland, Texas, and ICC exams above. Michigan requires 75%. Virginia lists a passing score of 60 on its 80-item portion.
When can I take the master exam? It depends on your state. In Texas, you need a journeyman license held for 2 years, or 1 year plus a U.S. Department of Labor–approved apprenticeship, and fingerprints. That requirement dropped from 4 years on September 1, 2025. (TSBPE master plumber page; TSBPE notice)
What does it cost? It varies. Examples: Colorado $78 ($73 to retest); Virginia $125; Maryland $65; Michigan $100; Texas a $25 TSBPE processing fee plus a $128.50 Pearson VUE exam fee; ICC G24 $120. Check your authority's fee page before paying, since fees change.
Does passing get me the license? Not by itself. You still complete licensing with your authority. In Texas, for example, there's a separate license fee.
Are paid practice tests worth it? Only if they match your exam. Before you buy, check that the material names your jurisdiction, uses your code edition, covers your official outline, explains answers with code references instead of just scoring them, and makes claims you can check against your bulletin. A big question count doesn't help if it trains you on the wrong edition.
Related free Castleport resources
- Plumber license requirements by state — use this when you still need to identify the licensing authority or master/contractor path in your state.
- Journeyman plumber exam prep — useful if you are preparing for the journeyman-level exam rather than a master-level exam.
Sources and editorial information
By Castleport Test Prep Editorial Team. Last verified: October 2, 2026 (official exam facts and OSHA rules).
The sizing drills state their own data and rules; they aren't code-table values from any edition. AI tools helped draft this page and check sources. It has not been reviewed by a licensed plumber.
- Colorado: PSI State Plumbing Board Candidate Information Bulletin, updated Sept. 3, 2026: format, calculator, books, code edition change, fees, retakes, outline.
- Virginia: PSI Individual License and Certification Candidate Information Bulletin, July 23, 2026: plumber portion, outline, references, fees, retakes.
- Maryland: PSI Master Plumber/Gas Fitter Qualification Information Bulletin, Aug. 10, 2026: format, outline, references, fees.
- Michigan: PSI Bureau of Construction Codes Candidate Information Bulletin, effective Apr. 29, 2026: master plumber format, references, marking rules, fee.
- Texas: Pearson VUE TSBPE Candidate Handbook, Aug. 2025; TSBPE master plumber page; TSBPE Master Plumber Examination Application; TSBPE notice on the experience change, June 23, 2025; Texas Register proposed rules, Aug. 14, 2026.
- ICC National Contractor/Trades Examination Information Bulletin, June 30, 2026, and ICC: what is a passing score?
- OSHA: 29 CFR 1926.451, 1926.651, and 1926.652 (eCFR).
Castleport Test Prep is an independent exam prep publisher. We are not affiliated with, endorsed by, or approved by the International Code Council, IAPMO, PSI, Pearson VUE, or any state plumbing board or agency named here. Exam, code, and credential names are used only to identify them; trademarks belong to their respective owners. The practice questions are original and unofficial. They're study material, not installation instructions, and they don't guarantee passing or a license.
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