Chimneys and Vents: Inspection and Testing Requirements

The special inspection requirements for chimneys and vents can be found in the 2022 NYC Building Code, Section 1705.32, with the testing requirements found in the 2022 NYC Fuel Gas Code, Section 503.5.6 and the 2022 NYC Mechanical Code, Section 810. The 2022 code update expanded this section to also include vents. Previously, in the 2014 code, the special inspection only referenced chimneys. The 2022 code clarifies that fuel fired appliances like boilers, water heaters and fire places would be subject to the same pressure testing, as per the test method described below.

New chimneys or vents must be visually inspected to verify compliance with the approved construction documents, and proper clearance or isolation from adjacent combustible construction. Existing chimney or vent passageways must be examined to ascertain that they are clear and free of obstructions and must be cleaned if previously used for venting solid or liquid fuel-burning appliances or fireplaces.

If a new heating system appliance is installed (such as a boiler), but the existing venting is reused, a special inspection to verify the condition of the existing chimney lining and breaching will be required. Any deficiencies will be reported to the contractor and owner as part of the required inspection reporting.

Pressurized smoke testing is required on all chimneys and vents except for new and existing “Listed Type B” gas vents and “Type L” vents. These vents will still require visual inspections for the presence of a continuous inner wall, proper installation, and no damage or deterioration via readily accessible areas of the vent system, such as the appliance, tee caps, cleanout openings, or termination. The vent system shall be inspected for proper clearances, protection and damage.

All new and altered chimneys and vents, and chimneys or vents to which a new appliance has been connected, shall be test run under operating conditions to demonstrate fire safety and the complete exhausting of smoke and the products of combustion to the outer air. To determine the tightness of chimney or vent construction, a smoke test shall be made in accordance with the following conditions and requirements:

1.        The equipment, materials, power and labor necessary for such test shall be furnished by, and at the expense of, the owner or holder of the work permit.

2.        If the test shows any evidence of leakage or other defects, such defects shall be corrected in accordance with the requirement of Chapter 5 of the 2022 NYC Fuel Gas Code and Chapter 8 of the 2022 NYC Mechanical Code and the test shall be repeated until the results are satisfactory.

3.        Method of test: The chimney or vent shall be filled with a thick penetrating smoke produced by one or more smoke machines, or smoke bombs, or other equivalent method. As the smoke appears at the stack opening on the roof, such opening shall be tightly closed and a pressure equivalent to ½ inch (12.7 mm) column of water measured at the base of the stack, shall be applied. The test shall be applied for a length of time sufficient to permit the inspection of the chimney.