Class B Practice Exam Questions And

Hawaii General Building Contractor (Class B) Practice Exam Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• Which of the following is the primary purpose of a building permit?
• To increase property value
• To ensure compliance with building codes
• To verify contractor qualifications
• To speed up construction

Answer: B. To ensure compliance with building codes

Rationale: A building permit ensures that construction meets safety,

zoning, and code requirements, protecting both occupants and the public.

• What is the minimum slope required for a residential roof to ensure

proper drainage? 1 / 4

• 1/4 inch per foot
• 1/2 inch per foot
• 1 inch per foot
• 2 inches per foot

Answer: A. 1/4 inch per foot

Rationale: Residential roofs typically require at least a 1/4 inch per foot

slope to allow water to drain properly and prevent pooling or leakage.

• Which type of soil is most prone to expansive movement that can

damage foundations?

• Sandy soil
• Clay soil
• Gravel
• Silt

Answer: B. Clay soil

Rationale: Clay soil absorbs water and expands, then contracts when dry,

which can cause foundation movement and cracking.

• When installing a concrete slab, what is the primary reason for

reinforcing with steel?

• To prevent cracking due to shrinkage and load
• To improve appearance
• To reduce weight
• To speed curing time 2 / 4

Answer: A. To prevent cracking due to shrinkage and load

Rationale: Steel reinforcement (rebar or mesh) strengthens concrete,

helping it resist tension, shrinkage, and structural loads.

• Which type of fire-resistant rating is required for a two-hour-rated wall?
• 30 minutes
• 1 hour
• 2 hours
• 4 hours

Answer: C. 2 hours

Rationale: A two-hour fire-rated wall must resist fire exposure for two

hours to help contain fire and protect occupants.

• What is the standard thickness for interior gypsum wallboard in

residential construction?

• 1/4 inch
• 3/8 inch
• 1/2 inch
• 5/8 inch

Answer: C. 1/2 inch

Rationale: Standard residential interior walls typically use 1/2 inch

drywall, which balances strength and ease of installation.

• Which of the following best describes the function of a vapor barrier in a

wall assembly? 3 / 4

• To provide structural support
• To prevent moisture from entering wall cavities
• To act as insulation
• To enhance paint adhesion

Answer: B. To prevent moisture from entering wall cavities

Rationale: A vapor barrier reduces moisture infiltration, preventing mold,

rot, and structural damage.

• How often should scaffolding be inspected by a competent person?
• Weekly
• Daily
• Monthly
• Before each shift

Answer: D. Before each shift

Rationale: OSHA requires scaffolds to be inspected for safety hazards

before each work shift and after any incident that could affect integrity.

• What is the primary purpose of a footing in foundation construction?
• To anchor the building to the ground
• To distribute the load over a larger soil area
• To prevent water infiltration
• To support plumbing systems
• / 4