What is the SMACNA maximum allowable length for a flex duct run?
The maximum code length for flexible air duct is 5 feet for traditional commercial systems, though some jurisdictions or project specs allow up to 6 feet . Flex duct should only be used for the final terminal connection to the diffuser-never as a substitute for hard trunk pipe.
['The maximum code length for flexible air duct is 5 feet for traditional commercial systems, though some jurisdictions or project specs allow up to 6 feet . Flex duct should only be used for the final terminal connection to the diffuser-never as a substitute for hard trunk pipe.']
Use this as training guidance. The foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, and AHJ/code requirements always control the final answer.
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The maximum code length for flexible air duct is 5 feet for traditional commercial systems, though some jurisdictions or project specs allow up to 6 feet . Flex duct should only be used for the final terminal connection to the diffuser-never as a substi
Steps
Stop and verify the approved detail, manufacturer instructions, foreman direction, and project specs before touching it.
The maximum code length for flexible air duct is 5 feet for traditional commercial systems, though some jurisdictions or project specs allow up to 6 feet. Flex duct should only be used...
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what is the smacna maximum allowable length for a flex duct run?