Author Topic: attic insulation question  (Read 2118 times)


  • 5 O'Clock Shadow
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attic insulation question
« on: May 20, 2015, 10:18:05 PM »
I'm getting ready to blow some more insulation in my 1950s ranch attic this weekend. My attic has about 10 inches of insulation, and I'm going to be adding another 15 inches of insulation to bring the value to R-50.

Prior to putting doing the insulation I sealed all gaps and spaces as best I could with Great Stuff. I went through five cans, and hopefully this will make a different of sorts. I'm wondering if it is safe to blow insulation on the gable sides of the attic, as I had a vapor barrier installed two years ago when I had Hardie Plank siding installed. As of now, there is no insulation along this area, and you can see down to the exterior walls in some places.

Any advice would be greatly appreciated. Peter


  • Walrus Stache
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Re: attic insulation question
« Reply #1 on: May 21, 2015, 08:57:10 AM »
What do you mean by "safe"? Safe from what?  Blown-in insulation is not a vapor barrier of any sort, if you're worried about moisture.


  • Handlebar Stache
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Re: attic insulation question
« Reply #2 on: May 21, 2015, 09:33:34 AM »
Yes it's safe and a good idea.


  • Magnum Stache
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Re: attic insulation question
« Reply #3 on: May 21, 2015, 09:41:07 AM »
It's advisable to have some sort of attic venting, though. They sell plastic tub-looking things that are supposed to leave enough of a gap in the insulation so that soffit vents still have access to the attic.