Dealing With Ice Dams

For most homeowners, cold winter weather is a good time to take a break from outdoor home maintenance projects.  However, homeowners should remember to keep a watchful eye out for the formation of ice dams on their roof.  Ice dams can cause serious damage to an asphalt shingle roof so it’s important to take action if you notice ice dams forming along the edge of your roof.  Otherwise, you may end up needing a new roof.

What Are Ice Dams?

Ice dams are a buildup of ice along the lower edge of a roof.  Ice dams form when snow and ice melt on warmer sections of the roof and the water freezes as it reaches the colder edges of the roof.  The ice forms a dam which causes more water to back up behind the dam.

What is The Harm From Ice Dams?

When water backs up behind an ice dam, it seeps under the shingles where it can leak into the home.  In addition, the water under the shingle will eventually freeze and since water expands as it freezes, it exerts pressure against the underside of the shingles causing them to loosen and split.

What Causes Ice Dams?

Ice dams form in weather conditions that allow snow and ice on the main area of the roof to melt, then re-freeze along the lower edge of the roof.  Ice dams usually don’t form if the weather is consistently cold because the snow and ice does not have a chance to melt. 

How Can Ice Dams Be Prevented?

Poorly insulated homes are more susceptible to ice dams.  The lack of insulation allows heat to escape from the home into the attic where it heats the underside of the roof and contributes to the melting snow and ice.  Adding insulation to prevent heat loss and ensuring that the attic has sufficient ventilation will reduce ice dam formation.  In addition, use a snow rake from the ground to clear as much snow from the roof as possible.  This will reduce the amount of melted runoff and also allow the sun to warm the edges of the roof. 

Posted on behalf of Ken Christie, CZE Roofing and Remodeling


Ice Dams

With winter weather just around the corner, it’s important to remember to keep an eye on your roof during the cold winter months for any signs of ice dams forming.  Ice dams form when snow on the warmer area of your roof melts, then re-freezes near the edge of the roof. 

Poor attic ventilation or insufficient attic insulation are the primary causes of ice dams.  What happens is that heat from your home escapes into the attic and warms up the main area of your roof.  If there is snow on the roof, it will begin melting and the runoff will flow to the edge of the roof.  The eaves are the edge of the roof that sticks out past the exterior walls of your house.  Your eaves hang out into the cold air and are not warmed by heat escaping from your home.  The eaves are much colder than the rest of the roof and snowmelt will often freeze when it reaches the eaves, creating an ice dam. 

The ice dam will cause water to back up under the shingles and leak on the decking and into the house.  Some of this water will also freeze.  Since water expands as it freezes, it will cause your shingles to split and buckle.  Water leaking into your home can damage walls, floors, and ceilings. The moisture on your decking and in your attic will also lead to other issues such as wood rot, mold and mildew.

If you notice ice dams forming on your roof, call a reputable local roofing contractor who specializes in residential roof repairs right away.  They can advise you as to the best solution for ice dam issues.