DC Plumber study plan
DC Plumber · Give each week a clear focus.
8 weeks · About 7 hours per week
Plumbing Code and Regulations (DC Plumbing Code, adopted model code, and amendments)
Map the DC Plumbing Code structure chapter by chapter and mark which chapters carry the heaviest exam weight
Identify the adopted model code edition and list the DC-specific amendments that override it
Build a one-page index of the code sections covering administration, permits, inspections, and definitions
Practice locating 15 code sections by keyword in under two minutes each using the table of contents and index
Your checkpoint
A one-page DC code navigation index plus a log of 15 timed section-lookup drills with your times recorded
Plumbing Code and Regulations (DC Plumbing Code, adopted model code, and amendments) & Drainage, Waste, and Vent Systems
Read the drainage and vent chapters of the DC code and summarize sizing tables in your own shorthand
Explain the difference between a vent stack, stack vent, and vent stack through the roof without notes
Work 20 practice problems on trap arm length, slope, and fixture unit values
Compare DC amendments affecting drainage and venting against the base model code text
Your checkpoint
A written summary of drainage and vent sizing rules with 20 solved practice problems showing your work
Drainage, Waste, and Vent Systems & Water Supply and Distribution Systems
Diagram a full DWV layout for a two-bath dwelling, labeling every trap, vent, and cleanout
Size water supply piping for a small commercial buildout using fixture units and developed length
Distinguish wet venting, common venting, and circuit venting with a hand-drawn sketch of each
List the code requirements for trap primers, cleanout spacing, and vent terminal height above roof
Your checkpoint
A hand-drawn DWV and water supply riser diagram for a sample two-bath dwelling with all pipe sizes annotated
General Plumbing Knowledge, Materials, and Fixtures & Fixtures, Fixture Fittings, and Water Heaters
Catalog approved pipe materials and their joining methods, noting where each is prohibited or restricted
Compare fixture types (water closets, lavatories, sinks, urinals) by code-required clearances and fixture-unit values
Explain water heater installation rules including T&P relief valve discharge, seismic strapping where applicable, and expansion control
Identify fixture fitting requirements such as backflow protection on hose bibs and supply stops
Your checkpoint
A materials and fixtures comparison chart covering at least 10 materials and 8 fixture types with governing code citations
Backflow Prevention, Cross-Connection Control, and Potable Water Protection & Water Supply and Distribution Systems
Define cross-connection, backflow, backsiphonage, and backpressure with a real plumbing example of each
Classify backflow prevention assemblies by type and identify where each is required in DC
Trace a potable water system from meter to fixture and mark every point needing a backflow device
Explain testing and inspection intervals for reduced pressure zone assemblies and double check valves
Your checkpoint
A marked-up potable water schematic showing every required backflow prevention device with the code basis for each
Fuel Gas Piping and Gas-Fired Appliances & Fixtures, Fixture Fittings, and Water Heaters
Outline fuel gas piping sizing methods and the rules for pipe support, protection, and underground burial
Explain combustion air requirements and venting categories for gas-fired appliances
List clearance-to-combustible and connector requirements for water heaters and furnaces
Identify the required tests for gas piping systems before and after being placed in service
Your checkpoint
A fuel gas installation checklist covering sizing, support, combustion air, venting, and pressure testing with code references
Safety, Tools, and Job-Site Practices & Plumbing Code and Regulations (DC Plumbing Code, adopted model code, and amendments)
List job-site safety requirements for trenching, confined spaces, soldering, and solvent cement use
Identify the correct tool and procedure for common tasks such as pressure testing, pipe cutting, and drain cleaning
Review the code administration chapter again and practice permit and inspection scenarios
Work 30 mixed practice questions across all eight domains and log every miss by domain
Your checkpoint
A safety and tools quick-reference sheet plus a scored 30-question mixed practice set with a written error log
Plumbing Code and Regulations (DC Plumbing Code, adopted model code, and amendments) & Drainage, Waste, and Vent Systems & Backflow Prevention, Cross-Connection Control, and Potable Water Protection
Re-drill every missed question from the week 7 error log until each is answered correctly twice
Take two full-length timed practice exams under exam conditions and record domain-level scores
Review the highest-weight domains one final time using your own index, charts, and diagrams
Confirm exam-day logistics including test location, identification requirements, and permitted reference materials
Your checkpoint
Two completed timed practice exams with domain score breakdowns and a one-page final review sheet of your weakest five topics
Milestones
Week 2: Can locate any drainage or venting code section in under 90 seconds and explain trap arm and vent terminal rules from memory
Week 4: Riser diagram is complete with correct pipe sizes, and the materials chart cites a code section for every entry
Week 6: Can explain backflow assembly selection and gas piping pressure testing without notes, scoring at least 70 percent on a self-made 20-question quiz
Week 8: Scores at least 80 percent on both timed practice exams with no single domain below 70 percent