Ice Dams Causes

What Are Ice Dams and What Causes Them?

One dreaded term for all New England homeowners is ice dams. Especially during the winter, there is no more fear inducing term when it comes to the health of your roof and attic. Ice dams are difficult to fix, however, they are preventable with some forethought going into the winter months. Proper roof ventilation, especially in older homes, is paramount to combat ice dams during the winter months. For instance, proper ventilation ensures there are no hot or cold spots in your attic or on your roof. These areas of temperature variability are the root cause for ice dams. Below you’ll find some information on ice dams and how they relate to your winter roof preparation.

What is an Ice Dam?

Ice dams are ridges, or dams, of ice that form on the lower edges of your roof. Just as the name implies, these ridges dam melting snow and water from shedding off of your roofing system. Additionally, roofs and shingles are designed to shed water to the ground or nearby gutters. Therefore, they are not meant to hold water for extended periods of time. As a result, during the winter, the water that remains, freezes, causing the dams. As more snow is thawed, the dams grow larger and larger. This can make them much more difficult to remedy and remove.

What Causes Ice Dams?

Ice dams are caused when a portion of your roof is heated from the inside, melting the layer of snow on top. This is often an unintentional heating, meaning it comes from an area with poor ventilation or insulation; therefore, it only affects a portion of the roof. When this happens, the melted snow travels down to areas that are still below freezing. In these areas, the water combines with freezing snow and causes ridges of solid ice. As this continues to happen for an extended period of time, more ice grows, creating a dam of water behind it. As more and more water backs up, these dams continue to grow and have a higher potential to cause leaks and rot to your roofing system.

What Causes Roof Rot?

When water is trapped on your roof for an extended period of time it can lead to rot and mold creation. This water can not only loosen shingles, causing issues for later, but also get beneath them and permeate the roof beneath. This often leads to rot and mold production in nothing only your roof, but attic and walls as well. Ice dams can cause shingles to lift, which not only causes immediate issues, but can leave your roof open to further leaks down the road. Combatting these issues early can prevent long term roof issues. By spending the time and money early, you can prevent the need for extensive repairs or early roof replacements down the line.

The University of Minnesota offers some great information and tips. For example, one tip involves creating and ensuring proper attic ventilation, a service we are very familiar with at Ranch Roofing. For more help, or to schedule an estimate for repair, contact us today!

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