Commercial Building Inspector B2Wall Construction and Wall CoveringsMedium
A commercial building inspector is examining a fire-resistance-rated shaft enclosure in a multi-story building. The shaft is rated for 2 hours. What is the minimum fire-resistance rating required for a fire door assembly installed in this shaft enclosure?
- A1.5 hours
- B0.5 hours
- C2 hours
- D1 hour
Show answer & explanationAnswer & explanation
Correct answer: A. 1.5 hours
For fire door assemblies installed in a 2-hour fire-resistance-rated shaft enclosure, the minimum required fire protection rating for the door assembly is 1.5 hours.
Why the other options are wrong
- B. 0.5-hour doors are typically for 1-hour fire partitions or smoke barriers.
- C. 2-hour doors are generally used in 3-hour fire walls.
- D. 1-hour doors are typically for 1-hour fire barriers or exit access corridors.
Fire Door Rating (Shaft Enclosure)
The minimum fire protection rating required for a fire door assembly installed in a fire-resistance-rated shaft enclosure.
- Shaft enclosures are critical for vertical fire separation.
- Door rating is typically less than, but related to, the wall rating.
- IBC Table 716.5 outlines these requirements.
Memory trick: Shaft's strength, door's defense, rating's reference.