801.16.1 Residential and low-heat appliances (general).
MC § 801.16.1
Flue lining systems for use with residential-type and low-heat appliances shall be limited to the following: 1. Clay flue lining complying with the requirements of ASTM C 315 or equivalent. Clay flue lining shall be installed in accordance with the New York City Building Code.
2.Listed and labeled chimney lining systems complying with UL 1777 (new and existing chimneys) or ULC-S635 (existing chimneys) or ULC-S640 (new chimneys).
3.Other approved materials that will resist, without cracking, softening or corrosion, flue gases and condensate at temperatures up to 1,800°F (982.2°C).
4.Existing firebrick chimneys may be used to vent appliances if the firebrick is acid resistant and lab tested. The brick and mortar must be inspected in accordance with Section 1705.32 of the New York City Building Code.













