Commercial Building Inspector B2General Administration, Permits, and PlansEasy
A commercial building inspector is reviewing plans for a new 5-story office building. The plans indicate that the building will be constructed using noncombustible materials for the structural frame, walls, floors, and roof, but will have a 2-hour fire-resistance rating for the structural frame. What type of construction does this building most likely represent according to the IBC?
- AType IV
- BType III-A
- CType I-A
- DType II-A
Show answer & explanationAnswer & explanation
Correct answer: D. Type II-A
Type II-A construction requires noncombustible materials throughout and a 1-hour fire-resistance rating for structural elements, with some exceptions. A 2-hour rating for the structural frame aligns with the general noncombustible nature but exceeds the minimum for II-A, making it a safe classification within Type II.
Why the other options are wrong
- A. Type IV (Heavy Timber) construction uses large dimension combustible lumber for structural elements.
- B. Type III-A allows exterior walls of noncombustible construction and interior elements of any material permitted by code, contrasting with the all noncombustible description.
- C. Type I-A requires higher fire-resistance ratings (e.g., 3-4 hours for structural frame) than specified.
Type II-A Construction
A type of construction where the building elements are of approved noncombustible materials and have a 1-hour fire-resistance rating, except as otherwise permitted by the International Building Code.
- All building elements are noncombustible.
- Structural frame and bearing walls generally require a 1-hour fire-resistance rating.
- Commonly used for office buildings, schools, and retail where moderate fire resistance is needed.
Memory trick: Imagine a 'II' as two noncombustible pillars, with 'A' meaning they are 'Always' protected for an hour.