Dick Nystrom appears on KARE11 News, discussing ice dams in Minnesota winters.
“Look at the pretty icicles.” You may have noticed long icicles hanging from your roof or gutters and not realize the significance of the damage that may be occurring behind them. Icicles are usually one of the first warning signs of possible ice dams on your roof.
What is an Ice Dam? An ice dam is wall or ridge of ice that forms at the edge of the roof at the gutters or soffit. When an ice dam forms, the melting water backs up behind it, creating a pool. It is this pool of water that causes the damage as it penetrates the roof and begins leaking into the home.
What Causes Ice Dams? Ice dams are usually caused by improper ventilation in the attic. This causes warmer areas in your attic then the snow begins to melt, even when the outside temperature is well below freezing. When the accumulated snow on your roof starts melting it runs down your roof underneath the snow until it reaches a "colder" section like the soffits, valleys or in gutters then it begins to freeze again, this process of thawing and refreezing is what causes an ice dam.
How to Prevent Ice Dams in the Future The best way to prevent future ice dams is to make sure your attic is properly ventilated and insulated. A licensed contractor should be referred to in order to make sure these repairs are done properly and up to Minnesota code.