|Typical Roof Temp - http://www.fsec.ucf.edu|
So, with this engrained in my head since the beginning of my HVAC time, I have preached this cardinal sin for duct layout for years: until today. I have finally seen a situation that I could not argue with, granted a very expensive solution. When the roof deck is spray foamed, the surface temperature of that insulation is much closer to the attic, which is now within the building envelope! I would still argue that this is not the way to secure the duct, as avoiding the use of flex duct in this type of layout could go a long way.
What do you think about ducts in an attic? I find they are a huge efficiency drain, sucking money from a homeowner's pocket year round. Equipment must be larger, there will always be leakage, most attics are not ideally vented, and never mind the IAQ issues! I was once with a contractor that found multiple dead animals in an attic that caused a stench like no other, sucked in through leaky returns and evenly distributed through out the home. Is the answer to remove attic ducts as an option, via code? Maybe eliminate attics?