AC Duct

[krarno]

What are the problems with installing duct work on top of a flat roof and is it legal?

[tech45]

People do it every day...weather and heat infiltration are the biggest issues that need to be considered when fabricating / installing .

[krarno]

Thanks tech45
We have a situation where the installation looks like a preying mantis on top of this house. Are there any issues regarding codes that you are aware of?

[J_SIN]

on a residential install? I cant imagine that looking like anything but crap. just out of curiosity, what state is this in?

[krarno]

Florida

[tech45]

I'd have to guess that this could just be a " free for all " ...no smoke / fire damper issues , no outside air requirements...just " run what you brung ". As long as the structure penetrations are firestopped I can't think of anything.

[motoguy128]

I would definitely look at some sort of minisplit system, rather than place ductwork on the exterior of the home. Seems like you could also do a PKG unit and install ductwork in the corners of the walls at the ceiling and drywall frame around them. But that might be worse yet.

[Gunnery Sergeant Hartman]

Pictures or it didn't happen!

[ACFIXR]

The minimum insulation value is r-8 for exterior duct in az, and im sure its the same there.Heat gain is a huge problem and so is the jumbo sized duct after you have r-8 insulation in it.