GAMP Exam Domains 2026: Complete Guide to All 12 Content Areas

Overview: The 12 GAMP Domains

The Georgia Master Plumber License Exam (Class II Unrestricted) - GAMP for short on this site - is not a single undifferentiated pool of plumbing trivia. PSI, which administers the exam on behalf of the Georgia State Division of Master and Journeyman Plumbers within the Georgia Construction Industry Licensing Board, builds the test from twelve defined content areas, each with a fixed percentage weight. Understanding those weights is the single most efficient thing you can do before you open a code book, because it tells you exactly where your study hours pay off and where they don't.

This guide breaks down all twelve domains, explains what each one actually tests, and shows how the weighting should shape a realistic prep schedule. If you haven't yet reviewed the baseline eligibility rules, start with GAMP Requirements 2026: Eligibility, Prerequisites & How to Qualify before you dive into content - there's no point mastering Domain 5 if you're not yet eligible to sit for the exam.

The Heavy-Weight Domains You Cannot Skip

Four domains sit at 10.71% or higher, and together they make up nearly half the exam. Get these wrong and no amount of skill in the smaller domains will save your score.

Mid-Weight Domains: Pipe Work, Design, and Planning

The next tier covers domains between 5% and 7.14%. They're smaller individually but still represent dozens of scored questions combined.

Lighter Domains That Still Decide Your Score

Two domains carry the smallest individual weight at 3.57% each, but combined they still represent a meaningful chunk of scored items - and both are easy to underestimate because they feel "basic."

Question Format and Exam Structure

All twelve domains are tested through multiple-choice questions delivered on a computer at a PSI test center. The exam totals 140 scored questions plus 28 unscored pretest questions that PSI uses to evaluate future items - you won't know which questions are which, so every question deserves full attention. The test is split into two parts of 3.5 hours each, and it is closed book, meaning no code references at your seat; a silent, nonprogrammable calculator is the only tool permitted.

A final scaled score of 70 is required to pass. Because the exam blends recall-based questions (laws, administrative rules) with applied-scenario questions (installation sequencing, calculations, code-compliance judgment calls), your prep needs to cover both memorization and problem-solving. For a deeper breakdown of what "passing" actually means numerically, see GAMP Passing Score 2026: Exactly What You Need to Pass, and for a realistic sense of how difficult the format tends to feel for candidates, read How Hard Is the GAMP Exam? Complete Difficulty Guide 2026.

Code Basis: What Changed for 2026

Exam content is tied directly to specific code editions, and that reference point is shifting. For exams administered beginning May 1, 2026, GAMP content is based exclusively on the 2024 Georgia Plumbing Code and 2024 Georgia Gas Code with Georgia amendments. If you're studying from an older code edition or a generic national plumbing code, you're studying the wrong document - domain content in installation, testing, and design questions will reflect the current Georgia amendments specifically, not the base model code language.

This code shift interacts with the eligibility changes taking effect under the licensing law effective July 1, 2026. Applicants generally need five years of full-time plumbing experience, though Georgia Journeyman Plumbers licensed before March 1, 2025 only need two of those years as a Journeyman, while those licensed later need four years as a Journeyman. At least two years must be in unrestricted Class II work, and the application requires supervisor affidavits, identity and lawful-presence documents, and a background check. None of this is domain content per se, but it determines when you're eligible to sit - plan your domain study schedule around your actual eligibility date, not an assumed one.

Mapping Domains to a Study Timeline

Rather than studying domains in numerical order, allocate time proportional to weight, and cluster related domains together since they draw on overlapping knowledge.

Spacing your review across weeks like this lets you revisit heavy domains (5, 2, 7, 8, 10, 11) more than once before test day while still giving the lighter domains dedicated attention rather than last-minute cramming. For a more detailed week-by-week plan built around this same weighting logic, see GAMP Study Guide 2026: How to Pass on Your First Attempt. You can reinforce each week's domain focus with timed practice sets on our GAMP practice test platform, which mirrors the two-part, multiple-choice format you'll see at the PSI test center.

Domain Weight Comparison Table

If you're still weighing whether pursuing the license is worth the study investment given these twelve domains, Is the GAMP Certification Worth It? Complete ROI Analysis 2026 lays out the broader case, and GAMP Jobs covers who actually hires Class II unrestricted license holders once you pass. For a full cost breakdown covering the application, exam, and renewal fees tied to these requirements, see GAMP Certification Cost 2026: Complete Pricing Breakdown.

Frequently Asked Questions