Insulation, Radiant and Vapor Barriers - Insulation Bats facing the right way

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Greg29
09-30-07, 10:22 PM
I have a Modular 2800sqf Colonial built in 2000, it has R38 insulation in the attic. The Batts have the paper on top so that you can read them when you look at them from above. From the reading I have been doing, I thought the paper should be down to form a vapor barrier.
I'm also thinking of adding insulation to beef up the R38 to R57 with an additional layer R19. My question is if the existing layers run in the joists East to West, should the new R19 run North to South over the joists. Any help and suggestions would be appreciated.
Thanks
Gregory

Ed Imeduc
09-30-07, 11:53 PM
Yes the paper side should be to the room . Up there the paper down to the ceiling. Id take and blow cellulose on top of what you have if you want more. If you use a roll kind you dont want any paper on it at all. Dont for get to add foam vents to the over hang if you dont have them now. So vent air from the over hang get up into the attic.
adamplghtg
10-01-07, 07:12 PM
Yeah I would add blown-in cellulose also. You will pay a little extra for it but it will do a much better job sealing the cracks and it will add more R-value.

Greg29
10-01-07, 10:02 PM
The idea adding cellulose appeals to me, but I have to 4x8 pieces of plywood on each side of the middle of the house, they run the full 48 foot length of the house. Do I need to tear them up or can I spray the cellulose underneath.
Thanks
Gregory
adamplghtg
10-02-07, 06:21 AM
Unless you can shove the hose down the full 48' of plywood then work your way back when you start filling, then it might be easier to cut out a couple of 1' sections about 20' apart. Blow one direction first then do the other. This will allow you to blow easier then reseal it after with the cut plywood. Be careful when you blow. Cellulose works best when you pressure pack it so it doesn't settle so have someone watching the ceiling below to make sure nothing bad happens. The average machine at the hardware store probably doesn't have enough pressure to cause problems so you should be OK but just have a second person to watch it anyway. Also watch for leaks. Cellulose is great at filling up any holes it sees.