California CSLB Class B General Building Trade Exam: free practice test
The trade exam for California's most popular license class. It tests building practice, framing and structural work, finish trades, safety and estimating, all from memory.
Watch the free 4:05 video lesson: the key CSLB Class B concepts →
- Lesson 2: Estimating and TakeoffsEstimating questions are math problems: volumes, areas, lumber, piece counts and pricing.
- Lesson 3: Site Work and FoundationsThis topic covers grading, footing size and depth, anchoring the building to the foundation, and crawl space access and venting.
- Lesson 4: Concrete and Moisture ControlConcrete questions test slab and footing minimums, reinforcing cover, and how water content affects strength.
- Lesson 5: Framing and StructuralThis topic covers wood framing rules for joists, studs and plates, and the limits on cutting framing members for pipes and wires.
- Lesson 6: Stairs, Guards and EgressThis topic covers stair geometry, handrails, guards and emergency escape openings.
- Lesson 7: Core Trades CoordinationA B contractor coordinates plumbing, electrical and mechanical work, so the exam asks basic layout and installation rules from the California Plumbing Code (CPC) and California Electrical Code (CEC).
- Lesson 8: Fire Safety and FinishesThis topic covers fire separation between the house and garage, fireblocking, safety glazing and common finish materials.
- Lesson 9: Jobsite Safety (Cal/OSHA)California jobsites follow Cal/OSHA rules in Title 8 of the California Code of Regulations, which are sometimes stricter than federal OSHA.
Keep going after the free lesson. Every topic gets its own lesson, plus the full question bank, timed simulations and study tools.
About the CSLB Class B exam
The trade exam for California's most popular license class. It tests building practice, framing and structural work, finish trades, safety and estimating, all from memory.
What's on the exam
Each branch is a topic in the official outline. Members see every key fact on the full mind map. Read the free study guide →
How to pass the CSLB Class B exam
- The B license requires work involving at least two unrelated trades (framing and carpentry don't count). Expect scope-of-license questions.
- Learn residential code numbers by heart: stairs, guards, egress, anchor bolts, fireblocking.
- Practice board-foot and concrete math without a reference book.
Save your results and get your Readiness Score
Create a free account after the test: your score by topic, a mistakes bank, the first study-notes topic, flashcards and the Construction Math Formula Sheet.
What's in the full CSLB Class B prep
Full question bank
6,100+ exam-style questions written to each official outline. Every answer explained, with the rule it comes from.
Timed exam simulator
Real question counts and time limits, so test day feels like practice day.
Exam Readiness Score
One 0 to 100 number that tells you when you're ready to book. Reach 80 and you're covered by our Pass Guarantee.
Flashcards + spaced repetition
530+ cards that come back right before you'd forget them. Five minutes a day keeps every number fresh.
Key study notes
Each topic boiled down to the 5 to 7 facts that get tested, with the statute or code section.
Mind maps
See the whole exam on one screen: every topic and the facts under it.
Sample questions with answers
These are the questions in the free test above, with answers. Try the test first. You'll learn more by getting some wrong.
1. A Class B General Building contractor may take a prime contract for a project that involves:
2. The B-2 Residential Remodeling classification covers residential improvement projects that involve at least:
3. Under the residential code, sill-plate anchor bolts must be at least 1/2 inch diameter, embedded at least 7 inches into concrete, and spaced no more than:
4. The maximum riser height for a stairway in a one- or two-family dwelling under the California Residential Code is:
5. Residential handrail height, measured vertically from the tread nosing, must be:
6. In a dwelling, guards are required where a walking surface is more than how far above the floor or grade below?
7. An emergency escape and rescue opening above grade floor must have a minimum net clear opening of:
8. In concealed wall spaces of stud walls, fireblocking is required vertically at ceiling and floor levels and horizontally at intervals not exceeding:
9. Fire-rated gypsum board used for rated assemblies is typically:
10. How many board feet are in one 2 × 12 that is 16 feet long?
11. Adding more water to a concrete mix (raising the water-cement ratio) will:
12. Hold-down hardware at the ends of a shear wall primarily resists:
13. The minimum thickness of a residential concrete floor slab on ground is:
14. A vapor retarder placed under a residential slab on grade is typically:
15. A straight or extension ladder should be set so that the base is out from the wall by about:
Get the full CSLB Class B prep
All-Access Monthly
- All 12 exams, including state Business & Law
- Full question banks + timed simulations
- Study notes, flashcards & mind maps
- Spaced repetition + mistakes bank
- Readiness Score & detailed reports
- Video lessons as they release
- New exams added during your access
- 5 bonuses: formula sheet, tabbing guide, study planner and more
- Pass Guarantee: complete the prep, pass or 100% back
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All-Access Yearly
- All 12 exams, including state Business & Law
- Full question banks + timed simulations
- Study notes, flashcards & mind maps
- Spaced repetition + mistakes bank
- Readiness Score & detailed reports
- Video lessons as they release
- New exams added during your access
- 5 bonuses: formula sheet, tabbing guide, study planner and more
- Pass Guarantee: complete the prep, pass or 100% back
Renews once a year until you cancel. We email you before each renewal. Cancel any time from your account; you keep access until the end of the year you've paid for.
Licensing guide
How to Get a Contractor License in California (2026): To get a California contractor license, you need at least four years of journey-level experience in the last 10 years, a $450 application to the Contractors State License Board (CSLB), and passing scores on the Law and Business exam plus a trade exam for most classifications. After you pass, you pay a $200 or $350 initial license fee, file a $25,000 contractor bond, and file workers' compensation coverage or an exemption. You need a license for any job of $1,000 or more in labor and materials, or any job that needs a building permit.
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Exam details are summarized from the official candidate information available in October 2026. Boards change formats and fees, so confirm with Contractors State License Board (CSLB) before you book. ContractorConquer is not affiliated with any licensing board or testing company.