Squeaky Floors and HVAC Lines
How to silence a squeaking duct
I decided to get rid of my squeaking floors, which were nailed down, not glued. When I pulled up a small section,
I found HVAC supply lines running between the ceiling and flooring joists. The squeak is actually the joist crushing the supply. I've pulled up the decking, but what do I do from there? There is no space for play between joists. You can barely fit a finish nail between the top or bottom joist and the supply.
— Andy, Arlington Heights, IL
Tom Silva replies: You have a couple of choices. You could hire a ductwork contractor to remove and resize the ducts. They would have to be made about half an inch smaller in both width and height than the old ducts. You need to replace only the duct in the section of the floor that is causing the problem. This may be more or less work depending on the extent of the ductwork and the noise problem.
Alternatively, you could remove the ductwork altogether and use the bay itself as a duct, lining it with drywall or metal.