Why walls loose so much heat

As insulation is put into walls you can see how it is pushed in. Two issues that creates problem in walls when it comes to this application. One is that the top and bottom and be jammed in such a way that the "fluffiness" which gives the insulation it's R factor can be lost. The second problem is that as time goes by the insulation can slough downward leaving a gap of an inch or two at the top. This is a very important area due to the fact heat rises and that is where the most insulation is needed.