For this reason faced insulation is typically installed on the.
Fiberglass insulation vapor barrier installation.
Since some leakage of moisture into the insulation in inevitable murphy s law you want it to be able to freely escape from the insulation into the attic.
The paper creates a vapor barrier that helps keep the water vapor in the warm moist heated indoor air from migrating outward into the wall or other structure.
It can be blown in polystyrene or fiberglass batts.
When installing your vapor barrier it is important not to compress your fiberglass insulation because they need to remain fluffy in order to keep its r value.
Vapor barriers in attics should only be installed on one side of the insulation.
To the inside of the home or the outside of the home.
If you install fiberglass batt insulation with a kraft paper vapor retarder in a home which way do you face the vapor retarder.
Installing vapor barrier over your head.
Vapor barriers are sheets of plastic or other material placed on one side of insulation sheets.
Faced means with built in kraft paper on one side that is used to form a vapor barrier.
Fiberglass batts are the most common.
For many building science questions the answer is it depends for this one the answer is clear.
If the insulation is installed with the paper vapor barrier facing away from the heated part of the home moisture from humid inside air can condense and become trapped in the insulation during cold winter months.
The paper should face the inside of the home.
In any case the vapor barrier must point to the warm side.
Wall insulation can come in different types.
First install the fiberglass insulation between the studs and then apply the vapor barrier over the installed fiberglass insulation.
Never compress or fluff your insulation.
Be sure the paper surface faces out into the room.
A smart vapor retarder is able to adapt its permeability to allow the wall to dry should moisture get trapped in the wall cavity.
Not be trapped inside.
The facing on kraft faced insulation is made of kraft paper with an asphalt coating that makes the paper impermeable to water vapor.
Cover the unfaced fiberglass wall insulation with a 3 mil polyethylene vapor barrier.
Consult an insulation professional in your area if you are unsure where or how to install a vapor retarder or consider a vapor retarder that provides some degree of additional flexibility like a smart vapor retarder.
The purpose of insulation facing.
This barrier is meant to keep moisture from getting to the insulation in the walls and ceilings and it is required by building codes when insulating most houses.