I added 9" of insulation to the exsisting 6" this past fall. I also bought and used one of these insulating tents. Over the course of the winter, I noticed a big dip in the amount of snow on my roof, right above the attic stairs and a big ice dam forming. All my heat loss was funneled to that area and melted a lot snow. I can not get a good seal around the bottom of the tent. It just uses it's own weight to stay in place and it's impossible to seal the gaps. This spring, I will build an insullating box over my stairwell. Does anyone want to buy a slightly used insulating tent, cheap?