Dealing with Ice Dams – Stop Water Damage From Snow Covered Roofs

With the extremely heavy snowfall that the mid-Atlantic has seen this season, ice dams are becoming a common problem. Ice dams occur when when melting snow and ice refreeze around the gutter line of a roof and prevent water from flowing off the structure, thereby creating a dam. This dammed up pool of moisture then sits at the edge of the roof. Roof coverings like shingles and shakes are not designed to protect the structure in this situation. A typical roof system is designed to protect the structure from falling precipitation and quickly move it off the structure. When an ice dam occurs it’s like submerging your roof under water. The system can’t handle the constant presence of water and the higher pressure from the water mass, so the water forces through the shingles and eventually through to components that will be damaged by moisture, like insulation and drywall.

The physics behind why these occur revolves around the heating and freezing cycle. Snow melts at the peak of the roof because warm air rises inside the structure. When temperatures drop at night the water freezes at the gutter line.  Run this cycle out a few days and you can end up with a significant amount of ice.
What to do if you have an ice dam? There are a couple of steps to deal with an ice dam if you have immediate issues.

First is to get the snow off the roof. Caution! Any person on the roof during the winter or performing work on the roof from below is risking injury. You can also cause serious damage to the roof and the house. If you believe you have an ice dam forming on your roof, contact professionals. Snow removal companies or seasonal businesses like landscapers often provide snow removal from roofs.

The only safe thing a homeowner can do that will not damage the house is to create a channel through the dam to get the pool of water off the roof. This can be accomplished with a garden hose on an above freezing day. Work up from the bottom of the dam spraying it with a focused stream.  Eventually the water will melt a groove in the dam and allow the pool of water to flow off the roof. This is, however only a temporary fix as the dam will reform quickly if the snow is not removed from the structure. This will stop the water damage in the home and give you time to contact a roof professional to alleviate the problem.

In the next article we will address preventative steps you can take so you won’t have to deal with ice dams next year.