Ice Dam

What is an Ice Dam?

Ice Dam

An ice dam is a ridge of ice that forms at the edge of a roof and prevents melting snow (water) from draining off the roof. The water that backs up behind the dam can leak into a home and cause damage to walls, ceilings, insulation, and other areas.

Effects of ice dams

If the snowfall has been heavy, or a large amount of ice has accumulated, the amount of water that enters the home can be significant enough to cause major drywall damage. If the drywall begins to bubble and turn yellow, most likely this drywall will need to be removed.

Moisture entering the home from ice dams can lead to the growth of mold and mildew. These can cause respiratory problems.

ice dam roof leak

What causes ice dams?

Nonuniform roof surface temperatures lead to ice dams.

Heat loss from a house, snow cover and outside temperatures interact to form ice dams. For ice dams to form there must be snow on the roof and, at the same time, higher portions of the roof’s outside surface must be above 32 degrees F (freezing) while lower surfaces are below 32F. These are average temperatures over sustained periods of time. For a portion of the roof to be below freezing, outside temperatures must also be below freezing.

The snow on a roof surface that is above freezing will melt. As water flows down the roof it reaches the portion of the roof that is below 32F and freezes. This causes the ice dam.

The dam grows as it is fed by the melting snow above it, but it will limit itself to the portions of the roof that average below 32F. So the water above backs up behind the ice dam and remains a liquid. This water finds cracks and openings in the exterior roof covering and flows into the attic space. From the attic it could flow into exterior walls or through the ceiling insulation and stain the ceiling finish.

Ice Dam
Ice Dam Roof Diagram

How to Get Rid of Ice Dams Fast

Disaster Repair Services

Our team is fully equipped to make all repairs to your property following a fire or water loss. We take care of every detail from top to bottom, inside and out including damage estimates, loss reporting, architectural services, permit expediting, and lender notifications.

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