Matt Fellman
11-19-2009, 11:52 PM
I'm getting conflicting info on this one. Are flexible ducts allowed to be installed in a concealed space - like in a floor joist bay that runs between two finished levels in a house?
I had never really thought about it since I don't see a lot of concealed spaces as I inspect houses but I'm running ductwork for an addition I'm putting on and can't get a straight answer.
Duct supplier says no they have to be sheetmetal (big surprise, he sells sheet metal and fabricates ducts). A couple calls to local HVAC contractors left me more confused then when I started. Just lots of 'maybe'
An inspector friend in a neighboring county to where I live said no problem as long as they're not penetrating a fire separation wall.... of course.
Anyhow, the attached pictures are of the metal ducting at the end of the existing house which I plan to tap into and extend to the new rooms (pictured at framing stage). Flex ducts would be much easier.... I'm calling my AHJ in the morning. I'm just curious what you guys think.
I had never really thought about it since I don't see a lot of concealed spaces as I inspect houses but I'm running ductwork for an addition I'm putting on and can't get a straight answer.
Duct supplier says no they have to be sheetmetal (big surprise, he sells sheet metal and fabricates ducts). A couple calls to local HVAC contractors left me more confused then when I started. Just lots of 'maybe'
An inspector friend in a neighboring county to where I live said no problem as long as they're not penetrating a fire separation wall.... of course.
Anyhow, the attached pictures are of the metal ducting at the end of the existing house which I plan to tap into and extend to the new rooms (pictured at framing stage). Flex ducts would be much easier.... I'm calling my AHJ in the morning. I'm just curious what you guys think.