- Exam Overview: How the Domains Fit Together
- Domain 1: Sitework, Footings and Foundation
- Domain 2: Concrete and Concrete Reinforcement
- Domain 3: Masonry
- Domain 4: Carpentry
- Domain 5: Roofing
- Domain 6: General Code and Construction Knowledge
- Domain 7: Associated Trades
- Domain 8: OSHA Safety
- Domain Weight Comparison
- Scheduling Your Study Time by Domain
- Where Candidates Lose Points
- FAQ
- The Residential-Basic trade exam has 80 questions across 8 domains, with a 200-minute limit and 70% passing score.
- General Code and Construction Knowledge is the single largest domain at 22.5% of the exam.
- Carpentry (20%) and General Code and Construction Knowledge (22.5%) together make up nearly half the test.
- Masonry is the lightest domain at 6.25%, but every domain still requires solid, exam-ready knowledge.
Exam Overview: How the Domains Fit Together
The Georgia Residential-Basic Contractor License Exam (GARBC) is administered by PSI on behalf of the Georgia State Licensing Board for Residential and Commercial General Contractors, Residential Contractors Division. Candidates seeking Residential-Basic licensure must pass two separate computer-based exams: the 80-question Residential-Basic trade exam within a 200-minute window, and a separate 50-question Business and Law exam within 120 minutes. Each exam requires a 70% score to pass, and PSI may seed either exam with unscored experimental questions that look and feel like the rest of the test.
This guide focuses on the trade exam - the one built from the 8 content domains listed below. These domains cover the physical, code-based, and safety knowledge required to build detached one- and two-family residences and one-family townhouses up to three stories, plus accessory structures. If you haven't confirmed you meet the underlying eligibility rules yet, review the GARBC requirements before diving into domain-level prep, since experience documentation and licensure timing affect when you can actually sit for the exam.
Domain 1: Sitework, Footings and Foundation (10%)
Sitework, Footings and Foundation
This domain tests your understanding of site preparation, excavation, soil conditions, and the footing and foundation systems that support a residential structure before framing begins.
- Soil-bearing capacity and how it dictates footing size and depth
- Grading, drainage, and erosion-control basics around the building envelope
- Foundation wall types, waterproofing, and frost-depth requirements as applied to Georgia residential construction
Because this is the first phase of any residential build, questions here often connect directly to Domain 2 (concrete) and Domain 6 (code knowledge) - expect the exam to test how these pieces interact rather than in isolation.
Domain 2: Concrete and Concrete Reinforcement (10%)
Concrete and Concrete Reinforcement
This domain covers concrete mix design, placement, curing, and the reinforcement methods used in slabs, footings, and foundation walls.
- Reinforcing steel placement, rebar sizing, and lap requirements
- Slab-on-grade construction, vapor barriers, and control joints
- Curing methods and common failure points such as cracking and settling
Expect scenario-based questions that ask you to identify the correct reinforcement approach for a given foundation condition rather than simple definition recall.
Domain 3: Masonry (6.25%)
Masonry
The smallest domain on the exam, Masonry still requires working knowledge of brick, block, and stone systems used in residential construction.
- Mortar types and their appropriate applications
- Veneer versus load-bearing masonry systems
- Flashing and weep-hole placement to manage moisture in masonry walls
Key Takeaway
Don't skip Masonry because it's the lowest-weighted domain - at roughly 6.25% of an 80-question exam, it still accounts for approximately 5 questions, which can matter when you're near the 70% threshold.
Domain 4: Carpentry (20%)
Carpentry
Carpentry is the second-largest domain and covers the full framing sequence from floor systems to roof framing, plus finish carpentry concepts.
- Floor joist spans, header sizing, and load-path fundamentals
- Wall framing, bracing, and shear requirements
- Stair layout, rise/run calculations, and guard/handrail requirements
- Roof framing basics that overlap with Domain 5
Given its 20% weight, Carpentry deserves a dedicated study block of its own. If you're building a week-by-week plan, pair your Carpentry review with the broader strategy outlined in the GARBC study guide, which walks through pacing an 80-question, 200-minute exam.
Domain 5: Roofing (10%)
Roofing
This domain tests roof system selection, installation sequencing, and the details that prevent leaks and structural failure.
- Roof pitch, framing types, and truss versus rafter systems
- Underlayment, flashing details, and ventilation requirements
- Shingle and roofing material installation standards
Roofing questions often test sequencing - what happens first, second, and third in an installation - rather than isolated fact recall, so practicing full roof-system scenarios pays off more than memorizing terms in a list.
Domain 6: General Code and Construction Knowledge (22.5%)
General Code and Construction Knowledge
This is the largest single domain on the GARBC trade exam, covering the code-based knowledge that ties every other trade domain together.
- Applicable residential building code provisions for the structures within Residential-Basic scope
- Permit, inspection, and approval sequencing
- General construction terminology and specification reading
- How code requirements apply differently to detached one- and two-family homes versus three-story townhouses
Domain 7: Associated Trades (12.5%)
Associated Trades
This domain covers the trades that intersect with residential general contracting even though a Residential-Basic licensee doesn't perform the specialty work directly.
- Basic plumbing rough-in and fixture placement concepts
- Electrical rough-in basics and coordination points with framing
- HVAC system placement and its impact on framing and code compliance
You're not expected to be a licensed electrician or plumber to pass this domain - you're expected to know enough to coordinate trades and avoid code conflicts on a residential job site.
Domain 8: OSHA Safety (8.75%)
OSHA Safety
This domain covers jobsite safety practices relevant to residential construction sites.
- Fall-protection requirements around foundations, framing, and roofing
- Personal protective equipment standards
- Excavation and trenching safety
Safety questions tend to be more straightforward than code or carpentry scenarios, making this a domain where consistent review typically produces reliable gains for the roughly 7 questions it represents.
Domain Weight Comparison
Here's how all 8 domains stack up against the 80-question trade exam, with approximate question counts based on each domain's percentage weight:
| Domain | Weight | Approx. Questions (of 80) |
|---|---|---|
| General Code and Construction Knowledge | 22.5% | ~18 |
| Carpentry | 20% | ~16 |
| Associated Trades | 12.5% | ~10 |
| Sitework, Footings and Foundation | 10% | ~8 |
| Concrete and Concrete Reinforcement | 10% | ~8 |
| Roofing | 10% | ~8 |
| OSHA Safety | 8.75% | ~7 |
| Masonry | 6.25% | ~5 |
These four domains - General Code and Construction Knowledge, Carpentry, Associated Trades, and the trio of Sitework, Concrete, and Roofing - collectively account for the majority of your score. For a deeper look at how the 70% threshold interacts with domain weighting, see our breakdown of the GARBC passing score.
Scheduling Your Study Time by Domain
Rather than studying all 8 domains equally, allocate time proportional to weight. A candidate with roughly 8 weeks before their scheduled exam date might structure review like this:
General Code and Construction Knowledge
- Work through code provisions relevant to Residential-Basic scope
- Review permit and inspection sequencing
Carpentry
- Practice framing load-path and span problems
- Drill stair and guard/handrail calculations
Associated Trades and OSHA Safety
- Review plumbing, electrical, and HVAC coordination points
- Study fall-protection and PPE requirements
Sitework, Concrete, and Roofing
- Connect foundation, footing, and slab concepts
- Review roof sequencing and flashing details
Masonry and Weak Spots
- Cover masonry mortar and veneer concepts
- Revisit any domain where practice scores lagged
Full-Length Practice and Timing
- Simulate the 80-question, 200-minute format
- Confirm open-book reference tabs are organized per PSI rules
This sequencing front-loads the two heaviest domains while still leaving room to reinforce weaker areas before test day. Timing your registration around this plan is worth doing early - check the GARBC exam dates guide so your study schedule lines up with an actual testing window and your one-year approval period.
Where Candidates Lose Points
Most candidates who fall short of 70% don't fail because they skipped a domain entirely - they fail because they underestimated how the heaviest domains are tested. A few recurring patterns:
- Treating General Code and Construction Knowledge as "background" material. At 22.5% of the exam, it needs dedicated scenario practice, not just a quick skim of code references.
- Under-preparing Carpentry math. Span tables, stair calculations, and load-path questions require practiced problem-solving, not memorized definitions.
- Assuming open-book means easy. PSI's permanent-tab and no-loose-paper rules mean you need your references organized before you sit down - flipping through an unmarked code book under time pressure costs minutes you don't have across 80 questions in 200 minutes.
- Ignoring Masonry and OSHA Safety. They're lightly weighted, but combined they still represent roughly 12 of the 80 questions.
For a broader look at what makes this exam challenging beyond just domain content, read how hard the GARBC exam really is. And if you want a condensed reference to keep the domain weights and key facts in front of you during final review, the GARBC cheat sheet is built for that purpose.
How These Domains Connect to Real Residential Work
The 8 domains aren't arbitrary test categories - they mirror the actual sequence and scope of a residential build governed by the Residential Contractors Division: sitework and foundation, then concrete, masonry, and carpentry framing, then roofing, with code knowledge, associated trades coordination, and safety practices running through every phase. Licensees who pass the Residential-Basic exam are approved to build detached one- and two-family residences and one-family townhouses up to three stories, plus accessory structures - which is exactly why the domain weighting favors Carpentry and General Code and Construction Knowledge so heavily. Those two areas govern the bulk of what a Residential-Basic contractor actually oversees on a jobsite.
Once you're licensed, maintaining it means renewing by June 30 of even-numbered years and logging 3 continuing-education hours annually through CE Broker - a detail worth keeping on your calendar well before your first renewal cycle. If you're still weighing whether the licensure path and its ongoing requirements make sense for your career, our analysis on whether the GARBC certification is worth it walks through that decision in more detail, and a full accounting of exam and application costs is available in the GARBC certification cost breakdown.
Whichever domain feels weakest right now, the fastest way to close the gap is repeated exposure to realistic, weighted questions. Spend time in full practice exams that mirror the 80-question structure before you commit to an actual test date.
Frequently Asked Questions
Question counts scale with each domain's percentage weight across the 80-question trade exam. General Code and Construction Knowledge (22.5%) contributes the most questions, roughly 18, while Masonry (6.25%) contributes the fewest, roughly 5.
No. The 8 domains covered in this guide belong to the 80-question Residential-Basic trade exam. The separate 50-question Business and Law exam, with its own 120-minute limit and 70% passing score, is not built from these same content domains.
Start with General Code and Construction Knowledge and Carpentry since they carry 22.5% and 20% of the exam respectively. Together they represent nearly half of the 80 questions, so mastering them first protects the bulk of your score.
Yes, both GARBC exams are open book, but PSI enforces permanent-tab and no-loose-paper rules. A silent, nonprinting, nonprogrammable calculator is also permitted, which is especially useful for Carpentry and Concrete calculations.
Yes. While OSHA Safety is its own domain at 8.75%, safety concepts like fall protection and trenching also surface contextually within Sitework, Roofing, and Carpentry scenario questions.