CSLB General Building (B): Core Trades
Section 3 of CSLB’s General Building (B) study guide · about 30% of the exam
110 questions across every section on the 3½-hour clock, with a score for core trades so you know where you stand.
Free core trades drillA plumber is installing a new hose bibb on the exterior of a house. What protection does the plumbing code require at this outlet?
Core Trades on the General Building (B) exam
Plumbing, electrical, HVAC, concrete, earthwork and surveying, insulation and weatherproofing, and roofing.
- Share of the exam
- About 30% (CSLB study guide); 33 of the 110 questions in our practice exam
- CSLB’s topics
- Plumbing · Electrical · HVAC · Concrete · Earthwork and surveying · Insulation, acoustical, and weatherproofing · Roofing
- Our drill
- 10 questions from 107 core trades questions, untimed, an explanation after every answer; one free attempt, unlimited with a pass
What core trades questions test
- Plumbing: drain, waste and vent basics, traps, water supply and water heaters
- Electrical: branch circuits, GFCI and AFCI protection, grounding and bonding, and working near energized parts
- HVAC: ducts, combustion air, venting and equipment clearances
- Concrete: footings and foundations, reinforcement and cover, mixing, placing, finishing, curing and cracking
- Earthwork and surveying: soils, compaction, grading and drainage, and setting out the building
- Insulation and weatherproofing: insulation, vapor retarders, sound control and waterproofing
- Roofing: underlayment, slope limits, flashing and roofing materials
Sit the full exam under the real clock
110 questions across every section on the 3½-hour clock, with a score for core trades so you know where you stand.
Free core trades drillHow to study it
- This is the largest section on the B exam (about 30%). A general building contractor coordinates every trade, so the exam tests what each trade must get right.
- Spend the most time on concrete and roofing, where most of the measurable rules sit, then plumbing and electrical basics.
Common questions
What is the largest section of the General Building exam?
Core Trades, at about 30% in CSLB’s study guide: plumbing, electrical, HVAC, concrete, earthwork and surveying, insulation and weatherproofing, and roofing.
Do I need to be an electrician or plumber to pass?
No. The questions test what a general building contractor needs to know to plan, coordinate and check the work of those trades, not specialty-license depth.
110 questions across every section on the 3½-hour clock, with a score for core trades so you know where you stand.
Free core trades drillThe other General Building (B) sections
Section topics and weight from CSLB study guide: General Building (B) (13E-B, 03-2026), checked November 2026.
Original independent practice questions written to CSLB’s published study guide outline. Not affiliated with or endorsed by the Contractors State License Board (CSLB) or PSI.