With only a short time to go before the return of spring, some parts of the country are still encountering freezing weather and snowstorms. With freezing and thawing temperatures, people in many parts of the country may encounter ice dams during these late winter months.
The U.S. Government’s Energy Star Program provides information about ice dams and how they form. The program states, “Ice dams usually occur after a heavy snowfall and several days of freezing temperatures. Warm air inside your home leaks into the attic and will warm the underside of the roof causing snow and ice on the roof to melt. The melted water will drain along the roof, under the snow, until it reaches the cold overhang. The overhang tends to be at the same temperature as the outdoors and the melted water will refreeze and form an ice dam and icicles. The ice dam can cause damage to the roof, which will result in water leaks to the inside. Frequently, the result will be a water spot on the ceiling under the roof damage.”
There are ways to help prevent the formation of an ice dam. A key factor is controlling heat loss from a building into the attic. Keep warm and moist air from entering the attic space from the interior of the building by sealing any air leakage pathways and be sure the attic is properly insulated. Vented appliances should be exhausted to outside of the building and not into the attic. Proper ventilation in the attic will also help to keep a uniform roof temperature.
“Water damage from an ice dam can leave behind more than just water stains on ceilings and walls,” said Jason Dobranic, Ph.D., Vice President of Microbiology and Life Sciences at EMSL Analytical, Inc. “The introduction of moisture can also result in mold growth. Even if the mold is in a ceiling or wall cavity, it could create indoor air quality issues for building occupants.”