Some have already seen some snow, and more is in the forecast – Winter is coming!

Ice jams are a hidden threat in Winter, and now is the time to take precautions to avoid them.

Ice jams occur when precipitation, such as snow, is in a pattern of melting and refreezing. Snow will melt as the temperatures climb during the day, and refreezes as the temperatures fall below freezing, forcing water and ice under shingles and the roof underlayment, potentially leading to leaking inside the home. There is more than likely nothing wrong with the roof, the problem is under the roof.

Inadequate insulation in your home allows heat to escape into your attic. As the heat in the attic reaches the roof, the roof deck warms and melts the snow on top of your roof. The melting and refreezing pattern causes a layer of ice to form under the snow on the surface of the roof, resulting in water leaking into your home and damage to the roof.

Proper soffit ventilation can help prevent this from happening. Rising air should enter the soffits and out the roof. But if there are not enough vents in the soffits, or the vents have become clogged with debris, cotton from trees, paint or insulation, they can act like a vacuum, sucking in moisture from the snow and forcing the warm air to warm the roof decking.

This illustration shows how an ice jam forms when the air isn’t properly directed.

The Rooferees offer these tips to avoid an ice jam from forming on your roof:

• Keep gutters and vents clean of visible debris

• Make sure soffit vents aren’t plugged with debris and dirt

• Make sure your home is properly insulated to avoid loss of heat

• Seal cracks and gaps where heat can escape, and caulk around windows

• The attic should have a few feet of insulation. If you are unsure if your home has enough insulation, have a contractor check it out

• Watch for icicles to form – they can be an indication of an ice jam

Ice jams can cause costly damage – take the time now to make sure your house is ready for winter!