A commercial building inspector is reviewing plans for a new 3-story Group S-1 storage building. The building will be equipped with an automatic sprinkler system throughout. What is the maximum allowable height for this building without height increases?
- A60 feet
- B50 feet
- C70 feet
- D40 feet
Show answer & explanationAnswer & explanation
Correct answer: B. 50 feet
According to IBC Table 504.3, for Group S-1 occupancy and Type II-A construction (which is implied as a baseline for a 3-story building with sprinklers, but the question asks for 'without height increases' from the base table), the basic allowable height is 50 feet. The presence of sprinklers allows for an increase, but the question asks for the maximum without 'height increases' meaning the base value from the table.
Why the other options are wrong
- A. 60 feet would be the allowable height with a sprinkler increase (50 ft + 20 ft = 70 ft, but limited by stories, so 3 stories * 20 ft/story + 10 ft for top story = 70 ft, or 50 ft + 20 ft = 70 ft, but the options are limited). The question specifically asks 'without height increases'.
- C. 70 feet would be the allowable height with a sprinkler increase for a 3-story building of Type II-A (50 + 20 = 70, but also depends on story count). The question asks for the base allowable height.
- D. 40 feet is typically for Type II-B or Type III-B construction for Group S-1.
Allowable Building Height (Basic)
The basic allowable building height is the maximum vertical dimension permitted for a building, measured from the lowest level of fire department vehicle access to the highest occupied floor. It is determined by occupancy group and construction type before any increases for sprinklers are applied.
- Determined by occupancy and construction type.
- Found in IBC Table 504.3.
- This is the 'base' height before modifications.
Memory trick: The 'Height Check' ensures the building doesn't overreach its base limits.