LICENSE EXAM QUESTIONS AND
CORRECT ANSWERS (VERIFIED
ANSWERS) PLUS RATIONALES 2025
1. What is the minimum headroom required for stairways in residential homes
in North Carolina?
A. 6 feet 4 inches
B. 6 feet 8 inches
C. 7 feet
D. 6 feet 6 inches
Rationale: The NC Residential Code requires a minimum stairway headroom of 6
feet 8 inches measured vertically from the sloped plane of the tread nosing.
2. What is the required slope for a drain pipe in a residential home?
A. 1/8 inch per foot
B. 3/8 inch per foot
C. 1/4 inch per foot
D. 1/2 inch per foot
,Rationale: A minimum slope of 1/4 inch per foot is required for drain pipes to
ensure proper flow and prevent clogging.
3. What is the allowable maximum spacing between balusters in a residential
guardrail?
A. 6 inches
B. 5 inches
C. 4 inches
D. 3 inches
Rationale: The building code specifies that a 4-inch sphere should not pass
through any opening in a guardrail to prevent children from slipping through.
4. Which of the following roof types is most prone to leakage?
A. Gable
B. Flat
C. Hip
D. Mansard
Rationale: Flat roofs have minimal pitch, making water drainage difficult and
increasing the potential for leaks.
5. What is the minimum required height of a residential guardrail?
A. 30 inches
B. 32 inches
C. 36 inches
D. 42 inches
Rationale: Guardrails in residential construction must be at least 36 inches in
height above the walking surface.
, 6. What is the typical lifespan of an asphalt shingle roof in North Carolina?
A. 10–15 years
B. 15–20 years
C. 20–25 years
D. 30–35 years
Rationale: Asphalt shingles generally last about 20–25 years, depending on
weather conditions and maintenance.
7. What is the proper way to vent a clothes dryer?
A. Into the attic
B. Into a wall cavity
C. To the exterior of the home
D. Under the crawl space
Rationale: Venting a dryer to the outside prevents moisture and lint buildup
inside the home, reducing fire and mold risks.
8. Which of the following is considered a structural component?
A. Drywall
B. Floor joists
C. Carpet
D. Wallpaper
Rationale: Floor joists are part of the structural framing system and support the
floor load.
9. What is the typical spacing for wall studs in residential construction?
A. 12 inches
B. 16 inches