Do you have huge icicles forming in your gutters and thick layers of ice at the edge of your roof? As common as these ice formations might be, they're not good for your home. Known as ice dams, these icy mounds are known to form when attics are poorly insulated. Snow melts on the warm roof, and the water trickles down before re-freezing along its edges.

Ice dams lead to a number of roofing issues. They can work their way under shingles, causing them to detach once the ice melts. They can also lead to water leaks, which may cause the underlying roof structure to mold and rot. If your home often forms ice dams in the winter, here are two actions you can take to fend them off.

Make sure your attic is insulated adequately.

If you don't have enough insulation in your attic, your roof will warm up, causing ice dams to form. How much insulation you need depends on your location. In most temperate climates, the Department of Energy recommends insulating to a value of R-60 in the attic. You can visit their website to see the specific recommendations for your climate zone. The R-value indicates the insulating ability of a specific insulation material. The higher the R-value, the more insulating the material.

If you have fiberglass insulation in your attic, look at the aluminum backing to read the R-value. If it below the recommended value for your area, adding an extra layer of insulation will help prevent ice dams. Estimating the R-value of existing blown-in or spray foam insulation is more difficult, and you will probably want to contact an expert to do this for you if you have one of these types of insulation.

Have your roof vents inspected (and possible improved) by a trusted roofing contractor.

Another major cause of ice dam formation is inadequate roof ventilation. Roofing vents that are installed incorrectly, clogged, improperly located, or not large enough may not let enough heat escape. Have a roofing company that you trust come out and take a look at your roofing vents, especially if you have ice dam problems in spite of a well-insulated attic. It will cost a lot less to have your vents evaluated and replaced than to replace an entire roof because water has leaked in and caused rotting.

Ice dams might look pretty, but they should not be ignored. If you let them reform season after season, you're likely to eventually have leaks and loose shingles to contend with. Take action now by addressing the two most common causes of ice dams – poor insulation and inadequate ventilation. If you still have ice dams after taking these two steps, you might want to have a roofing expert come out and do a full inspection. Other issues, such as the placement of exhaust systems and torn roofing membranes can also contribute to ice dam formation in rare cases. Talk to people like Whitaker Construction Group Inc. for more information.