Ceilings Protecting Steel Beams or Joists

What happens when there is no fire-protection material applied to steel beams or joists that support floors or roofs? ISO still considers a building modified fire resistive if it has a suitable ceiling.

Ceilings can be plaster or gypsum wallboard or suspended mineral tile.

The entire floor-ceiling (a fire-resistive ceiling protecting a floor) or roof-ceiling (a fire-resistive ceiling protecting roof supports) should conform to construction details in a UL-listed or Factory Mutual (FM)-approved design. ISO individually evaluates each approved design.

The drop ceiling is the fire protection for the beam
One-hour UL-listed assembly concrete on steel deck