All buildings shall be classified under four general types, according to the character of materials employed, their method of assembly, and the fire resistance which they afford as follows:
Type I – Fire-Resistive Construction.
Type II – Noncombustible Construction.
Type III – Exterior Protected Construction.
Type III-A – Heavy Timber.
Type III-B – Ordinary.
Type III-C – Ordinary.
Type IV – Combustible Frame Construction.
(Prior code § 49-1)