Icicles and Ice Dams: What to Know


Icicles are a standard part of winter, but the ornate spears of ice hanging from your roof could be part of a larger problem: an ice dam. Ice dams can be problematic in the winter due to their potential to cause roof damage and water damage as they melt. Though the presence of icicles isn’t always indicative of an ice dam, ice blocks can accumulate and grow along the eaves of the roof, on the gutter and create large icicles. These same blocks can become ice dams as snowmelt runoff continues to trickle down the roof and refreeze in the same places. With icicles, it is important to be aware of their size and location, monitoring any ice dam formation.

Ice Dam Risks

Ice dams can be minor problems or turn into more serious problems depending on how large they are, the temperature conditions outdoors, and how well your attic is insulated. All of these factor into how severe ice dams become and what their level of damage can be. While you can’t control the outdoor weather conditions, you can control the heat retention in your home. Making sure that the attic floor is airtight and properly insulated is important to retaining heat in the house and preventing excess heat from infiltrating the attic and melting snow and ice from the roof.

Ventilate and Insulate

Keeping heat where it belongs in the living quarters of the home and making sure that the attic is properly ventilated to prevent excessive heat buildup are the two most important ice dam prevention measures you can take. There are a number of ways to efficiently ventilate your attic–eave vents, soffit vents, ridge vents, gable vents, or some combination. Most modern roofs combine a ridge vent with soffit or eave vents to release any heat that penetrates the attic. Ensuring proper ventilation of the attic will reduce the likelihood of ice dams forming and leading to water damage.

Remove Ice Buildup

It is a good practice to remove thick ice that builds up along the eaves of the roof and gutter when possible. Thick icicles and blocks of ice can damage these components of your roof and lead to water damage as they melt. Applying ice melt to this ice buildup can help manage ice accumulation on the roof and prevent ice dams from becoming a problem. If ice dams are a serious problem every winter, you can consider installing heating strips to your roof to prevent ice buildup.