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 Duct testing is offered for new residential and commercial construction, HVAC contractors and home owners. We also do testing on replacement furnaces for code requirement.

A duct test will checks the leakage in the duct system. This test is required on all new construction and replacement of all furnaces.

Duct testing is done by sealing off and pressurizing the ventilation system. It will be tested with our equipment at 25 Pascals.

R403.3.3 Duct Testing (Mandatory)

Ducts shall be leak tested in accordance with WSU RS-33 using the maximum duct leakage rates specified. 

EXCEPTIONS: The total leakage test or leakage to the outdoors is not required for ducts and air handlers located entirely within the building  thermal envelope. For forced air ducts, a maximum of 10 linear feet of return ducts and 5 linear feet of supply ducts may be located outside the conditioned space. All metallic ducts located outside the conditioned space must have both transverse and longitudinal joints sealed with mastic. If flex ducts are used, they cannot contain splices. Flex duct connections must be made with nylon straps and installed using a plastic strapping tensioning tool. Ducts located in the crawl spaces do not qualify for this exception. 

A written report of the results shall be signed by the party conduction the test and provided to the code official. 

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