TYPES OF CONSTRUCTION
The majority of building codes divide buildings into classes based upon the manner of their construction, use, or occupancy.
The following division into classes applies to the manner of construction:
1. Frame construction.
2. Nonfireproof constructions:
(а) Ordinary construction;
(b) Slow-burning construction.
3. Fireproof construction.
Frame construction embraces all buildings with exterior walls of wooden framework sheathed with wood shingles or siding; veneered with brick, stone, or terra cotta; or covered with stucco or sheet metal. Such buildings naturally have floors and partitions of wood and are considered as comprising the most inflammable type of construction.
Nonfireproof construction includes all buildings with exterior walls of masonry but with wood floor construction and partitions. Slow-burning construction designates heavy timber framing designed as far as possible to be fire resistant, the heavy beams and girders of large dimension proving far less inflammable than the slender joists of ordinary construction.
Fireproof construction includes all buildings constructed of incombustible material throughout, with floors of iron, steel, or reinforced concrete beams, filled in between with terra cotta or other masonry arches or with concrete slabs. Wood may be used only for under and upper floors, window and door frames, sash, doors, and interior finish. In buildings of great height the flooring must be of incombustible material and the sash, doors, frames, and interior finish of metal. Wire glass is used in the windows, and аll structural and reinforced steel must be surroundеd with fireproof material, such as hollow terra cotta and gypsum tile to protect the steel from the weakening effect of great heat.