§ 27-819 Furnace supports.
AC § 27-819
Floor furnaces shall be installed only in floors of noncombustible construction having at least a two hour fire resistance rating, except as provided for one- and two-family dwellings in section 27-823 of this article. Floor furnaces shall have the following clearances: (a) Pit clearances. Floor furnaces, when other than gas-fired, shall be mounted independently of the floor grille with a six inch clearance at the bottom and a twelve inch clearance at the sides except that the clearance on the control side shall be at least eighteen inches.
(b)Pit waterproofing. When there is likelihood of water rising above the bottom clearance of the unit, the pit shall be constructed with a watertight enclosure with the sides extending at least four inches above the ground level.
