A commercial building features a large skylight in its roof assembly. The skylight opening measures 8 feet by 10 feet. According to IBC Section 2405.3, what is the minimum required amount of screening below this skylight, if the skylight is installed over a walking surface and the glazing is not fully tempered or laminated?
- AA screen capable of supporting 200 pounds applied over a 2-inch square area.
- BNo screening required if the glazing is annealed.
- CA screen capable of supporting 300 pounds applied over a 2-inch square area.
- DA screen capable of supporting 200 pounds applied over a 4-inch square area.
Show answer & explanationAnswer & explanation
Correct answer: A. A screen capable of supporting 200 pounds applied over a 2-inch square area.
IBC Section 2405.3 (and often 2405.6 for skylight screening) specifies requirements for screens below skylights where the glazing is not fully tempered or laminated and is installed over a walking surface. The code requires that such a screen shall be provided and be capable of supporting a 200-pound (90 kg) load applied perpendicularly to the screen over any 2-inch-square (645 mm²) area. This prevents falling glass from injuring occupants below in case of breakage.
Why the other options are wrong
- B. Annealed glass is not considered safety glazing for these applications and requires screening.
- C. 300 pounds is an incorrect load; the code specifies 200 pounds.
- D. 4-inch square area is incorrect; the code specifies 2-inch square.
Skylight Screening Requirements
Code-mandated screens installed below skylights over walking surfaces, designed to prevent injury from falling glass if the glazing is not fully tempered or laminated.
- Required by IBC Section 2405.3 (and 2405.6 for specifics).
- Applies to non-safety glazing over walking surfaces.
- Screen must withstand specific point loads.
Memory trick: Skylights need screens like safety nets under non-tempered glass.