(a) Except as herein provided, all chimneys in every building hereafter erected and all chimneys hereafter altered or rebuilt shall be constructed of brick, stone or reinforced concrete or Underwriters' Laboratories-listed approved chimney. No masonry chimneys shall have walls less than four inches in thickness, and all chimneys shall be lined on the inside with fireclay chimney tile set in Portland cement mortar or its equivalent. The lining shall be continuous from the bottom of the flue to its extreme height. No chimney shall be corbeled out more than six inches from a brick wall, and such corbeling shall consist of not less than five courses of brick, unless the chimney requires special construction, and then any specially constructed chimney shall not be corbeled out to such extent that the center of gravity of the chimney would be located so as to endanger the structure.
(b) All chimneys shall project at least three feet above the point of contact with a flat roof or two feet above any roof surface within ten feet horizontally of the chimney.
(c) The fireback of every fireplace hereafter erected shall not be less then eight inches in thickness of solid brickwork or air cell construction, nor less than twelve inches of stone lined with firebrick. When a grate is set in a fireplace a lining of firebrick at least two inches in thickness shall be added to the fireback, or soapstone, fireclay or cast iron may be used if solidly backed with brick or concrete. All smokepipes shall enter the chimney through a flue thimble or its equivalent such that the construction shall make a fire-tight joint with the chimney tile flue liner.
(d) All flue holes when not in use shall be closed with tight-fitting metal covers. No wooden beams or joists shall be placed within one inch of the outside face of the chimney or flue, whether the same be for smoke, air or any purpose, except for hot-air flues for heating purposes. No woodwork shall be within four inches of the back wall of any fireplace except if a chimney is built such that the thickness from the flueline is eight inches or more. Necessary woodwork may be placed against the chimney by using drywall sheeting or its equivalent between and around the wood so placed under the approval of the Fire Chief or his authorized representative. (Ord. 81-17. Passed 8-6-81.)