protected noncombustible construction

protected noncombustible construction

Noncombustible construction in which bearing walls (or bearing portions of walls), exterior or interior, have minimum fire-endurance ratings of 2 hr and are stable under fire conditions; roofs and floors, and their supports, have 1-hr fire-endurance ratings; stairways and other openings through floors are enclosed with partitions having 1-hr fire-endurance ratings.