Commercial Building Inspector B2Wall Construction and Wall CoveringsMedium
A commercial building inspector is reviewing the plans for a new loading dock entry. The opening is located in an exterior wall that is required to have a 2-hour fire-resistance rating. The building is classified as Type III-A construction. What is the maximum aggregate area of unprotected openings permitted in the exterior wall on any story?
- A25% of the wall area.
- BNo unprotected openings are permitted.
- C15% of the wall area.
- D10% of the wall area.
Show answer & explanationAnswer & explanation
Correct answer: B. No unprotected openings are permitted.
According to IBC Table 705.8, for a 2-hour fire-resistance-rated exterior wall in Type III-A construction, the maximum percentage of unprotected openings permitted is 0%. All openings must be protected.
Why the other options are wrong
- A. This percentage is applicable to other wall ratings or construction types, but not this specific scenario.
- C. This percentage is applicable to other wall ratings or construction types, but not this specific scenario.
- D. This percentage is applicable to other wall ratings or construction types, but not this specific scenario.
Exterior Wall Unprotected Opening Limits
The maximum aggregate area of unprotected openings permitted in an exterior wall is determined by the wall's fire-resistance rating, the building's construction type, and the fire separation distance.
- Limits prevent fire spread between buildings.
- Table 705.8 in IBC specifies percentages.
- 0% means all openings must be protected.
Memory trick: Exterior walls guard against fire, openings need a strict decree.