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An-drew
Attic Insulation

I'm a bit confused here. In trying to determine the proper way to insulate an old attic I've read that vapor barrier needs to face warm area, down or facing ceiling of lower room...and that you should use unfaced batting in the attics.

This video shows using faced insulation with the barrier being down but the description says to use unfaced insulation.

Here it also says to used unfaced insulation in the attic.

But I have read in several other places that a vapor barrier is needed if one is not present.

The house in question was built in the late 1800's to early 1900's with absolutely NO insulation anywhere. And it does get slightly cold here at times in Mid Georgia. I want to add insulation but I do not want to do it twice. So, the question is:

In an attic installation with no insulation do you use faced or unfaced insulation?

bsum1
Re: Attic Insulation
Shubi
Re: Attic Insulation
An-drew wrote:

I'm a bit confused here. In trying to determine the proper way to insulate an old attic I've read that vapor barrier needs to face warm area, down or facing ceiling of lower room...and that you should use unfaced batting in the attics.

This video shows using faced insulation with the barrier being down but the description says to use unfaced insulation.

Here it also says to used unfaced insulation in the attic.

But I have read in several other places that a vapor barrier is needed if one is not present.

The house in question was built in the late 1800's to early 1900's with absolutely NO insulation anywhere. And it does get slightly cold here at times in Mid Georgia. I want to add insulation but I do not want to do it twice. So, the question is:

In an attic installation with no insulation do you use faced or unfaced insulation?

Vapor barrier placement depends on where you live. If you live in the north with more heating days than cooling days, the vapor barrier goes towards the conditioned area. In the south with more cooling days, it is reversed. If heating and cooling days are equal, it becomes a judgement call. At any rate, the vapor barrier is not effective if it is not installed properly with no gaps. In any case, seal all bypasses from the conditioned areas before insulating. Common areas are around chimneys, DWV's interior walls, exhaust fans and recessed lights.

sabo4545
Re: Attic Insulation

If you are in a cold climate there should be a vapor barrier attached to the bottom of the ceiling joist (if kraft faced insulation is used the wings are stapled to the joists. However I feel that you are better off using plastic sheeting and un-faced insulation in-between the joists and taping all the joints or using acoustical sealant to seal up the plastic sheeting). Drywall is then attached to the ceiling joists.

The article is talking about adding additional insulation across the joists. In this case since you already have a vapor barrier you want to used un-faced insulation so as not to create two vapor barriers with insulation sandwiched in-between. Of course if you are in a warm humid climate where you use A/C a lot more than heating you want your vapor barriers toward the outside of the house. Hope this helps you out.

Mike

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