TinnerFlow™2nd YearFlex DuctYELLOW · Check First
Crushed flex is an airflow restriction, not a finish-detail inconvenience. Pull it out of the pinch point and use an approved rigid/alternate path that fits the wall cavity without choking the branch.
Flex duct cannot deliver air if the core is flattened, kinked, or smashed behind drywall. A wall that physically crushes the duct is telling you the material/path is wrong.
The fix is usually to stop cover, expose the pinch, and change the branch path or material: rigid wall stack, oval/rectangular metal, different boot location, or approved alternate route. Do not fight drywall around a crushed flex and hope air makes it through.
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.