Section 27-863. Chimney construction for low, medium, and high temperature equipment

(a) Unlisted chimneys for low temperature equipment shall  be  constructed in accordance with table 15-4.
    (b)  Unlisted  chimneys  for  medium  temperature  equipment  shall be
  constructed in accordance with table 15-5.
    (c)  Unlisted  chimneys  for  high  temperature  equipment  shall   be
  constructed in accordance with table 15-6.
 
            (For table 15-4 see chapter 839 of the laws of 1986)
 
    Notes:
    a  Metal  chimneys  shall be of riveted, bolted or welded construction
  and made gas tight.
    b Exterior metal chimneys shall  be  galvanized,  or  painted  on  the
  exterior  surface with a heat resisting paint or be constructed of equal
  corrosion resistive alloys.
    c In buildings in residential occupancy group J-3, of four stories  or
  less,  and  in other buildings not over two stories high and not in high
  hazard occupancy group A, providing the flue areas are not more than 200
  sq. in. the walls of masonry or concrete chimneys may be  reduced  to  4
  in.  with  fire  clay  flue  lining.  Flue linings shall be set ahead of
  chimney walls, and carefully bedded in fire clay  mortar  or  in  cement
  mortar. Chimney walls shall be provided with mortar spacer ties every 10
  ft.  of  height.  Mortar  ties  shall  not be continuous around the flue
  linings.
 
        (For tables 15-5&15-6 see chapter 839 of the laws of 1986)