I was thinking about adding another layer of insulation in the attic. The joist cavities are filled but they both are faced with a paper vapour barrier. The bottom or 1st layer is fylly faced while the 2nd layer just has the paper on one side (facing down) I was wondering if it would be ok to add another layer on top of these but going the opposite way. Also The person who added the 2nd layer covered up all of the soffit vents. the attic is 1200sq ft. i was going to put attic baffels in betwen the cavities where the vents are (13 of them). Do I just put them where the vents are locared or does it have to go into every cavity. The soffit vents are the only source of air intake. Lots of ways for the air to get out. Anyone ever heard of "gyproc wool insulation"? that's what the 1st layer is and I was just looking for info on it. circa 1950's. Thanks.

 

Mattmold,

This article will help with your project,

http://doityourself.com/attic/insatticvenilate.htm

Hope this helps!

 

They have just come out with one called Miraflex fiberglass Attic Blanket. Has a R 25 looks good and Home Depot and Lowes has it.
Id put the attic baffels or so called rafter vents . In every cavity so you let lots of air in there.. They now have them made out of foam now . ED

 

matt -

i'd recommend un-faced insulation. probably a bit
cheaper and you really only need and want one layer
of facing, at the very bottom.

definately ventilate! and open up those closed vents.

 

I have put in the attic baffels. Man, what a job! Trance, there is 2 layers of insulation in my attic already. the first is fully faced , the second is faced on 1 side only. faced side facing the living area. I was planning on adding a layer of unfaced insulation on top of the existing 2 layers. Sorry if I got mixed up in my description. I haver put in those rafeter vents in every cavity, and I'm going tonight to get the insulation. hope this finally lowers my heating bill.

 

Sounds good. I think for where you are they say a R-40 .

ED

 

the backing on the insulation is the vapor barrier, ALL VAPOR BARRIERS must face the WARM side of the room you are insulating. So the very first layer closest to the room should have the vapor barrier facing DOWN then the next layer or layers should NOT have a vapor barier. Cut the insulation 1-3inches longer for a snug fitting, make sure you have no gaps where air can get in. Clear all your soffits, dont plug any of them, and also, install a ridgevent so the air from soffit can escape!! it wont escape and enter through soffit. Heat rises. If you dont do these things, you could be looking at mildew and failure of the isulation to work properly. RaisinsFly