NHIE Building Systems and Components 2 — Questions and Answers
Question 1: What is the minimum recommended clearance between the bottom of floor joists and the ground in a crawl space?
- 12 inches
- 18 inches (Correct answer)
- 24 inches
- 6 inches
Correct answer: 18 inches
IRC and most standards require at least 18 inches of clearance between the bottom of floor joists and the ground in a crawl space to allow for inspection and ventilation.
Question 2: Which type of pipe material is identified by its blue or blue-striped color?
- CPVC
- PEX-B cold water (Correct answer)
- ABS
- Polybutylene
Correct answer: PEX-B cold water
PEX tubing for cold water lines is typically blue, while red indicates hot water lines, helping installers and inspectors quickly identify the system.
Question 3: When inspecting a gas furnace, which condition would indicate a cracked heat exchanger?
- Yellow pilot flame
- Rust staining on the burner
- Soot deposits near the flue collar
- Flame rollout when blower activates (Correct answer)
Correct answer: Flame rollout when blower activates
Flame rollout when the blower turns on is a classic sign of a cracked heat exchanger, as combustion gases escape into the air distribution system.
Question 4: What is the purpose of a P-trap in a plumbing drain system?
- Prevent backflow from the water main
- Hold water to block sewer gases from entering the home (Correct answer)
- Filter debris before it reaches the drain line
- Regulate water pressure in the drain
Correct answer: Hold water to block sewer gases from entering the home
A P-trap retains a small amount of water that acts as a seal, preventing sewer gases from passing through the drain and entering the living space.
Question 5: An inspector notices the main electrical panel has double-tapped breakers. What does this mean?
- Two circuits share one breaker (Correct answer)
- A breaker is installed upside down
- The panel is over-fused
- A tandem breaker is used correctly
Correct answer: Two circuits share one breaker
Double-tapping means two separate conductors are connected to a single breaker terminal, which is a defect unless the breaker is specifically rated for multiple conductors.
Question 6: What type of roof covering requires a minimum slope of 4:12 for proper installation?
- EPDM membrane
- Three-tab asphalt shingles (Correct answer)
- Standing seam metal panels
- Modified bitumen
Correct answer: Three-tab asphalt shingles
Standard three-tab asphalt shingles require a minimum roof slope of 4:12 to ensure proper water shedding and prevent moisture infiltration.
Question 7: Which condition in a basement wall is most indicative of hydrostatic pressure?
- Horizontal cracking in the middle third of the wall (Correct answer)
- Diagonal stair-step cracking at corners
- Vertical hairline cracks near the center
- Spalling of the concrete surface
Correct answer: Horizontal cracking in the middle third of the wall
Horizontal cracks in the middle third of a basement masonry or concrete wall are the most serious sign of hydrostatic pressure from saturated soil pushing inward.
NHIE Building Systems and Components 2
What is the minimum recommended clearance between the bottom of floor joists and the ground in a crawl space?