Have you ever looked out the window and noticed that some homes seem to have less snow on their roofs than others? Most of the time, the amount of snow on your roof isn’t a problem. However, homes that lose more heat through their roof space melt the snow faster and that can be a sign of insufficient insulation or poor ventilation. Does your roof have enough snow?
Ideally, a properly insulated home with adequate ventilation will have a cold roof space. Any heat or moisture that does get into the roof space should escape easily through the roof vents. If your house does not have enough insulation OR adequate ventilation, heat and moisture can be trapped in the roof space. This causes the roof space to heat up and melt the snow above.
In homes with plenty of insulation but poor ventilation, the roof space will still eventually warm. The heat cannot easily escape causing the snow to melt. The trapped moisture in a warm roof space can lead to wood rotting.
If your home has excellent ventilation but poor insulation, the wood in your roof will be protected but your heating bill will be higher. Heat and moisture will escape and not melt the snow except maybe near the outside walls. This area will be the warmest because the heat has not yet had a chance to escape. Snow that melts here and causes ice to build-up, may lead to leakage.
A well insulated and ventilated roof space will keep a healthy amount of snow on it and not have constant ice build-up. The next time after a good snowfall, have a look at your roof. Compare it with similar houses on the same side of your street. Comparing a house on the North side of a street to a house on the South side would not be a fair comparison because they get differing amounts of sunlight. If your home does not have enough snow, it might be worthwhile to call an insulation or roofing professional.