Attic hatch or door.
Insulate plenum attic.
Try r316 3 r316 4 r316 5 4 you might claim an exemption under r316 5 4 1 and 2 but could really piss an inspector off.
Insulating the plenum on a forced air system.
The plenum is about 7 feet long x 2 feet wide x 1 foot high.
Then you ve got r318 4 to consider.
Mine is an 80 furnace 92 ac.
Insulating exposed heating ducts in attics basements and under subfloors can improve the energy efficiency of a heating system.
Affix rigid foam insulation to the attic side of the hatch or door.
Especially applicable in humid southern climates.
This isa recently installed system performing well indoor humidity steady at 45.
I had to completely gut the existing hvac system in my 1991 house due to numerous major issues flex tubing like swiss cheese facing into the plenum kinks leaks a branch off the end of the trunk returns in the wrong place missing registers in some rooms too many in others etc.
6 8 insulated fleixible duct lines come off of the plenum.
My crawl space is averaging 72 humidity right now raleigh nc.
Add weatherstripping around the perimeter and a sweep to the door of a walk up attic.
Hello i have a difficult situation.
In this case the temperature gradient between supply air and the ceiling can be such that the duct surface could be cooler than the local dew point.
After ripping everything out in the house and basement now the trunk is.
Getting a new complete system inside and out.
One company is touting externally wrapped insulation for the metal plenums as their key value proposition over internally insulated metal plenums.
Describing the general internal insulation technique to stop your ac unit from sweating on the outside.
Pull down stair or ladder.
Use a zippered insulated tent to keep the enclosure draft free attic tent at 7 attic cover insulator 120.
Two other companies both use internally insulated and claim they are the way to go.
Should you always insulate the plenum on an attic furnace ac horizontal setup.
In a vented attic this can happen when the duct is in close proximity to conditioned space i e the ceiling and also thermally isolated from the hot attic beneath the ceiling insulation.
