Commercial Building Inspector B2General Administration, Permits, and PlansHard
A commercial building inspector is reviewing plans for a new 5-story Group B office building with a total floor area of 100,000 square feet. The building is of Type II-A construction. What is the maximum allowable area per floor for this building without area increases?
- A36,000 sq ft
- B24,000 sq ft
- C48,000 sq ft
- D18,000 sq ft
Show answer & explanationAnswer & explanation
Correct answer: B. 24,000 sq ft
According to IBC Table 506.2, for Group B occupancy and Type II-A construction, the basic allowable area per story (A_a) is 24,000 square feet. This value is before any increases for sprinklers or frontage are applied.
Why the other options are wrong
- A. 36,000 sq ft would be the basic allowable area for Type II-A, Group B, if it were a single story and had frontage increases (24,000 * 1.5 = 36,000).
- C. 48,000 sq ft is the basic allowable area for Type I-B construction, Group B.
- D. 18,000 sq ft is the basic allowable area for Type II-B construction, Group B.
Allowable Building Area (Basic)
The basic allowable building area is the maximum area permitted for a single story of a building, determined by its occupancy group and construction type, prior to any increases for automatic sprinkler systems or building frontage.
- Determined by occupancy and construction type.
- Found in IBC Table 506.2.
- This is the 'base' area before modifications.
Memory trick: The 'Area Assessment' starts with the building's core identity.