ductwork in attic

[theplumber]

should the ductwork in the attic be suspended above the insulation in the ceiling or placed directly on top of the ceiling joists and buried in the insulation when the attic is insulated? I am building a new house, thanks for any help you may have. I am insulating the attic with 15" of cellulose

[davesrha]

12" up from sheetrock is code for us

[tinner73]

i always hang it.

[ttstrutt]

I always run ductwork above the insulation, supported at least every 4 or 5 feet, if there is enough attic space. This helps prevent other trades from running their wires and pipes on top of the ducts and damaging the duct work.
The job looks cleaner and with flex duct it allows more room for a nice gradual sweep down to the boots, which helps reduce air restrictions.

[dash]

Code here is above insulation.

[theplumber]

thank you, I appreciate that, do you feel the ductwork is better buried in the insulation or suspended above the insulation?

[dash]

Florida study showed that the ducts ,with R-6 insulation ,displaced more ceiling insulation than it replaced(with the Duct R value) leaving the ceiling with less R value,hence the code.

Now if you could "bury' it under the full R value of ceiling insulation,it might be better,otherwise ,I'd do as Clint Eastwood,




"Hang Em High".

[theplumber]

thanks all for you help, I do appreciate that