A. Definition: The term "fireproof construction," as used in Chapters 1, 5, 8 and 9 of this Title, means a building in which all of the parts that carry loads or resist strains, and all exterior walls and all interior walls or partitions and all stairways and elevator enclosures are made of incombustible material, and in which all metallic structural members are protected against the effects of fire by being completely embedded in a material which shall be entirely incombustible and a slow heat conductor.
B. Specifications:
1. If the metal framework of a roof is not less than twenty five feet (25') above any floor or balcony, the roof framework may be protected by a suspended ceiling of metal lath and Portland cement plaster, not less than one inch (1") thick.
2. The fireproof covering on columns shall be not less than two inches (2") thick if of concrete or gunite, or three inches (3") thick if of other than approved material; on girders, not less than two inches (2") thick; and other structural parts, not less than one and one-half inches (11/2") inches thick. The thickness shall be outside the extreme edges of the structural members. The following building materials, systems, units and forms of construction, assembled and constructed or hereinafter required, shall be accepted as fireproof construction:
a. Plain or reinforced concrete;
b. Reinforced gunite;
c. Precast reinforced concrete units;
d. Hollow or solid concrete masonry units;
e. Brick (clay, sand-lime or concrete);
f. Hollow brick (clay, sand-lime or concrete);
g. Plain or reinforced gypsum;
h. Precast reinforced gypsum units;
i. Hollow or solid gypsum block;
j. Hollow clay tile;
k. Metal lath and Portland cement plaster
The order in which the foregoing materials are placed in the list is not to be construed as indicating their relative fireproof qualities.
3. All fire-resistive construction laid in units or blocks such as brick and hollow or concrete or clay tile, shall be solidly bedded and laid in Portland cement or cement-lime mortar as defined in Section 9-1-6-3 of this Chapter on mortar, and shall be thoroughly bonded together by means of broken joints in alternate courses, or by sufficient metal ties or bands; provided, however, that gypsum products shall be laid in gypsum mortar. (1964 Code § 285)
C. Hazardous Uses: Any building or structure intended to be used wholly or in part as a theater, auditorium, public garage or school, shall be constructed according to the specifications for fireproof construction set forth in this Chapter. Any building intended to be used as a hospital and which is more than one story in height shall be of fireproof construction, and any building to be used for storage of explosives or flammable liquids or for storing nitrocellulose, or for a dry-cleaning establishment, foundry or coffee roaster, shall be of fireproof construction. (1964 Code § 284)