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Okay to fiberglass insulation placed over minimal cellulose?

05/22/2001 04:26 PM lb

Hello,

31 year old house...2x4 trusses. About 2" of original cellulose insulation remaining from original job.

Can I just place fiberglass R-38 on top of the cellulose?

Should I use unfaced or faced, or the stuff that seems completely encapsulated?

Thanks for the help,

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Okay to fiberglass insulation placed over minimal cellulose?

05/23/2001 08:38 PM Jay J

Hi lb,

If I understand you correctly (and correct me if I don't), you have 2" of cellulose remaining and you simply want to know if you can cover it up w/R-38? In short, yes. It will render the 2" useless since it will get 'compressed'. Loose-fill insulation is meant to be loose. If you can, I would remove the 2". THen, I'd use FACED insulation (with the paper side FACING the heated part of the house.)

It sounds like an attic. What's the bigger picture here???

Jay J -Moderator

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Okay to fiberglass insulation placed over minimal cellulose?

06/09/2001 02:41 AM lb

Jay,

thanks...have been away for a while. Yes, this is an attic. I would rather not remove the existing cellulose insulation due to dust hazards, etc.

Sounds like it will not be a problem to place faced insulation on top of this (faced towards living space)?

Thanks for the help,

Lynn

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2 " of cellulose with faced batting

03/06/2005 02:26 AM lkellyhome

I am insulating my attic. there is 2' of cellulose that is very uneven and spotty. I want an R rating of 38+. Can I put two layers of unfaced batting or do I need one faced and one unfaced batting?

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pain to do right

03/12/2005 07:15 PM david_wv

The big question is whether there is a vapor barrier under the cellulose. I think that you have to have a vapor barrier to keep moisture from condensing in the insulation.

I recently went through scraping up shredded fiberglass loosefill, putting down faced batts, respreading the loosefill and then topping with a layer of batts.

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2" cellulose

03/14/2005 09:09 AM lkellyhome

There was no vapor barrier. I did not see any type of pare or plastic under the cellulose. I put R19 faced roll over and then R30 unfaced encapsulated roll batt on top. Will this work? Will I have to go back up there?

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don't know the answer to the last

03/19/2005 04:41 PM david_wv

I didn't want to take the chance of mold etc between the ceiling and the faced insulation. I could have put in a LOT of miserable work for nothing. It could be that the vapor barrier of the ceiling with its paint will be enough. Especially since the insulation on top will keep the cellulose warm so the vapor won't condense as readily.

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does cellulose hold moisture?

09/02/2005 04:49 PM emcspadden

I am thinking about insulating my 1908 house with cellulose (exterior walls and attic floor) and fiberglass (attic walls and ceiling). I should also mention that I have a moist basement with a mold problem (I am working on it, but the moisture problem will never be totally solved).

If I have cellulose blown into the cavities of the exterior walls and attic floor(without any mositure barrier in sight that I know of), will I be ok? Should the fiberglass insulation in the walls and ceiling of the attic be faced or unfaced? I am allergic to mold and am very paranoid about trapping mositure in my walls.

I sould also mention that I am having my house resided and rigid foam insulation without a moisture barrier is going up underneath the vinyl siding.

Thanks!

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