Section 713.3.2, Two-Hour Shaft Enclosures, of the IBC, is hereby established by adding the following section:
Section 713.3.2 Two-Hour Shaft Enclosures. Shafts that are required to have a fire resistance rating of 2 hours or more serving Interior Exit Stairs or Interior Exit Ramps shall be constructed of concrete or masonry for types III, IV and V construction. Interior Exit Stairs or Interior Exit Ramps in type I and II construction and all other shafts that are required to have a fire resistance rating of 2 hours or more shall be constructed of non-combustible materials.