Insulation..when is too much too much?

[bkelly2 (Brian Kelly, AZ Cert. # 60234)]

@tallen

Also from the link:

Blanket Insulation: Batts and Rolls
Installing batts and rolls in attics is fairly easy, but doing it right is very important. On unfinished attic floors, work from the perimeter toward the attic door. In new construction, the vapor retarder facing should be installed with the facing placed down toward the ceiling gypsum board, except in hot humid climates where unfaced batts should be used. If reinsulating over existing insulation, it is recommended that unfaced batts be used. If there is not any insulation in your attic, fit the insulation between the joists. If the existing insulation is near or above the top of the joists, it is a good idea to place the new batts perpendicular to the old ones because that will help to cover the tops of the joists themselves and reduce heat loss or gain through the frame. Also, be sure to insulate the trap or access door. Although the area of the door is small, an uninsulated attic door will reduce energy savings substantially. :mrgreen:

Vapor barrier faces the conditioned space. I understand diffusion, but what is humidity?

Don’t see batts so much any more, too labor intensive. Many of the newer homes have blown in fibre glass about 15 inches. I find I itch less inspecting attics wearing shorts. I’ll see if I have a picture.