With hundreds of square feet of ductwork surface area in the attic and a δt of 75 f the air coming out of the vents in your home will be significantly higher than 55 f.
Main ductork in attic.
Cut a piece of foil tape to length.
The duct insulation should include a vapor barrier cover.
If you re used to putting ducts in the attic moving the ducts indoors probably won t be easy by martin holladay august 3 2018 a vented unconditioned attic is a terrible place to locate a furnace and ductwork.
Here s bob s trick for taping a seam on a pipe that s installed close to the subfloor.
Throw duct leakage into the mix and the problems are even worse.
Type of ductwork system the least expensive duct system is a radial system of flexible ducts in an attic running to ceiling grates.
One side of the duct system blows air through the branch ducts while the other side pulls air in.
Use metal flex or fiber board ducts that are insulated to code.
Your first stop will be the main unit and its large ducts which are connected to the branch ducts that run throughout the house.
The answer is simple.
If they are located in your attic be sure the area is properly insulated and any cracks or holes are sealed.
The costliest are sheet metal ducts running in enclosed walls and ceilings.
When hvac ducts are installed in a vented attic in a dry climate bury the ducts in attic insulation to protect them from temperature extremes in the unconditioned attic space.
Ductwork running along an open ceiling in the basement of a one story home is also more affordable to replace.
Peel off part of the backing.
Yes when you bury ducts in attic insulation in a humid climate you increase the risk of water vapor condensation on the jacket of the duct insulation.
Slide the backing up and over the pipe.
Leave backing on the tape on metal ductwork.
If the ducts are going to be concealed all seams need to be taped or caulked.
As most gba readers know ducts belong inside a home s thermal envelope not in an environment that s cold in the winter.
Attics are almost as cold as the outdoors during the winter and can be much hotter than the outdoors during the summer.
If ducts are located in a crawlspace underneath your house cover the soil to reduce moisture.
You shouldn t install ducts in a vented unconditioned attic.
But in my last article i also showed you some preliminary results from a research study on buried ducts in a hot humid climate.
Turn your hvac system on and feel around all air duct connections for any air leaks.