CBI Cheat Sheet 2026

The 30 highest-yield CBI facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. When must a footing inspection be performed? → After excavation and forms are erected, but before concrete is placed
2. Under the International Building Code (IBC), what is the maximum travel distance to an exit in a fully sprinklered business occupancy? → 300 feet
3. What is the minimum headroom required above stair treads in a dwelling under the IRC, measured vertically from the sloped plane of the tread nosings? → 6 feet 8 inches
4. Radon gas in homes primarily originates from the natural decay of which element in soil and rock? → Uranium
5. Which building material is a common indoor source of formaldehyde emissions? → Particleboard and MDF
6. What environmental protection measure applies to maintenance protocols? → Proper handling, storage, and disposal of materials according to environmental regulations
7. In an exterior bearing wall, what is the maximum diameter of a bored hole in a single stud under the IRC? → 40% of stud width
8. Under the IRC, may a door from a garage open directly into a sleeping room? → No, openings from a garage directly into a sleeping room are prohibited
9. On a low-slope roof, OSHA allows a warning line system to be set back at least how far from the roof edge? → 6 feet
10. An inspector finds two conductors secured under a single breaker terminal that is not listed for two wires. How should this be reported? → A double-tap defect that can cause loose connections and overheating
11. Anchor bolts must be located within what distance of each end of a sill plate section? → 12 inches
12. What is OSHA's 8-hour time-weighted average action level for noise that triggers a hearing conservation program? → 85 dBA
13. Homes built before what year are presumed likely to contain lead-based paint? → 1978
14. An inspector holds a smoke source near a water heater draft hood and sees the smoke pushed outward into the room. What does this indicate? → Backdrafting or spillage of combustion gases
15. Which limitation of a non-contact voltage tester matters most to an inspector? → It can give false negatives, so it cannot prove a conductor is de-energized
16. A water heater temperature and pressure relief valve discharge pipe must terminate no more than how far above the floor or waste receptor? → 6 inches
17. What foundation type is best suited for expansive clay soils? → Pier and beam
18. What inspection procedure is essential for safety procedures? → Systematic inspection following established checklists and standards
19. Which procedure ensures machinery or electrical circuits stay de-energized while being worked on or examined? → Lockout/tagout
20. Heaving and upward cracking of a slab-on-grade in a region with clay soils is most commonly caused by what? → Expansive soils absorbing moisture
21. Why must an inspector warn against drilling or cutting into a post-tensioned concrete slab? → Severed tendons under high tension can fail violently and weaken the slab
22. Under NFPA 10, how often should portable fire extinguishers receive a visual inspection? → Monthly
23. Under the IRC, smoke alarms are required in which of the following locations? → In each sleeping room, outside each sleeping area, and on each story
24. Under the IRC, carbon monoxide alarms are required in new dwellings that have which condition? → Fuel-fired appliances or an attached garage
25. Which structure is typically exempt from a building permit under the IRC? → A one-story detached accessory structure of 200 sq ft or less
26. Which condition with a wood I-joist is a serious structural defect? → A notch cut through the bottom flange
27. Why is soil compaction important in foundation design? → It reduces foundation settlement
28. What is the minimum thickness of a concrete footing under the IRC? → 6 inches
29. An inspector observes foundation anchor bolts spaced 8 feet on center in a one-story dwelling. What is the IRC maximum spacing? → 6 feet
30. What is the minimum working space depth required in front of a residential electrical panel rated 600 volts or less with grounded parts across from it? → 36 inches