Commercial Building Inspector B2Public Safety and Special ConstructionMedium

A building inspector is reviewing the plans for a new six-story Group R-2 apartment building. The design includes a trash chute system. What is the minimum required fire-resistance rating for the enclosure of the trash chute?

  1. A1-hour fire-resistance rating
  2. B3-hour fire-resistance rating
  3. C2-hour fire-resistance rating
  4. D4-hour fire-resistance rating
Show answer & explanation

Correct answer: C. 2-hour fire-resistance rating

According to IBC Section 713.13.1, chutes and their enclosures extending through more than two stories are required to have a minimum 2-hour fire-resistance rating. A six-story building clearly exceeds this threshold.

Why the other options are wrong

  • A. 1-hour is typically for chutes extending through not more than two stories, which is not the case here.
  • B. 3-hour ratings are typically for specific fire walls or more hazardous shafts, not standard trash chutes.
  • D. 4-hour ratings are for very high hazard or specialized fire walls, which is excessive for a trash chute enclosure in this context.

Trash Chute Enclosure Rating

The minimum fire-resistance rating required for the enclosure of a trash chute, depending on the number of stories it penetrates, to prevent fire spread.

  • Based on the number of stories penetrated.
  • 1-hour for 2 stories or less.
  • 2-hour for more than 2 stories.
  • Must extend from the bottom to the top of the chute.

Memory trick: Tall chutes need strong walls to stop the flames from climbing.

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