If too much heat escapes through your attic, it can cause snow on your roof to repeatedly melt and refreeze, creating a thick ice dam that can cause serious damage. The solution is to top up your attic insulation. Start by measuring the depth of your insulation using a free Owens Corning ruler from The Home Depot. If the levels are less than 4 inches your attic needs to be topped up.
Rent an insulation blowing machine from The Home Depot Tool Rental Centre and use a loose fill insulation such as Atticat. Note that rental is free with the purchase of 10 or more insulation bags. This is an easy weekend project, and a 1,000 square foot attic can be completed in less than 4 hours.