How to insulate a vaulted ceiling (non-cathedral) attic floor?
I live in Climate Zone 2, Houston, TX. I am adding insulation to my attic to increase comfort and cut down on A/C. I realize that I need to airseal and preparation before insulation but I am stumped as to how to properly insulate my vaulted ceilings. I live in a 3 story condo. The 3rd floor’s ceiling is half vaulted ceiling, half flat. I can easily blow in insulation to the flat part.
What is the best, non-spray in foam, method to insulate the vaulted ceiling? If I blow in cellulose on top of the small amount of fiberglass that is already there, it is likely to tumble down the slope of the vaulted ceiling (but maybe not, thoughts?). I really want to blow in to get into all the nooks and crannies but it might not be possible. I also think that blow in will require less time than cutting all the batts to size, since the shapes and angles of the ceiling are very abnormal (see pics). However, I’ll go the hard work of the batt route if there is just no way to blow in the cellulose on the sloped vaulted ceiling/attic floor. I was thinking of maybe gently laying a mesh fabric (same thing that they use to insulate with blow-in prior to drywall) to “hold” the cellulose in place, so it won’t shift. This might be the same amount of trouble, though, as cutting the batts. Thoughts and advice?
1. Climate Zone 2
2. Trying to insulate Vaulted ceiling/attic floor
3. Slope approximately 30-35° (flatter than 45°) (see picture of inside)
4. Current insulation: R-19
5. Desired insulation: R-38
How to insulate the best?
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