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There is a problem with loose-fill fiberglass attic insulation in cold climates. It appears that, as attic temperature drops below a certain point, air begins to circulate into and within the insulation, forming "convective loops" that increase heat loss and decrease the effective R-value. At very cold temperatures (-20°F), the R-value may decrease by up to 50%. The problem was first documented twelve years ago at the University of Saskatoon in Saskatchewan. Using infrared thermography, researchers observed hexagonal cold patterns on the ceiling of a house insulated with cubed loose-fill fiberglass. They suspected that the cold spots were caused by air circulation within the insulation. In 1982, researchers at the Owens-Corning Fiberglas Research Station in Granville, Ohio, observed a measurable decrease in R-value when a full-scale