ICE DAMMING

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Find and fix this costly energy thief. By Joe Hurst-Wajszczuk

Icicles hanging along the eaves of a roof may be prettier than store-bought twinkle lights, but these sparkling natural beauties are a symptom of a major home ailment.

Icicles form when snow accumulates on the roof, melts and then refreezes at the roof's edge. This ice build-up is called "ice damming." Although the icicles themselves are harmless, the build-up prevents melting snow and ice from draining into gutters and off your roof. The blocked water can work under your roofing and into your home.

Once inside, water causes a host of problems you can and can't see. Some of the easiest problems to fix include gutters sagging from the weight of the ice, stained or Baggy ceilings, and loose roof shingles.

But the most serious problems are the ones you can't see. Water dampens and compresses wall and attic insulation, lowering R-values and increasing heating costs. Even small amounts of moisture feed nasty mold and mildew growths that can affect your health and lead to major structural damage in your house.

Even if you only get a few days of snow a year, you still need to watch out for ice dams. They can form from as little as 1 inch of snow, and once inside, the moisture can silently eat away at your home for years. Here are several ways you can protect your home from ice damming and address the symptoms, even in a blizzard:

Even if you only get a few feet of snow a year, you still need to watch out for ice dams.

PREVENTIVE MAINTENANCE

Ice clamming occurs because hot air from living spaces leaks into the roof space and melts the snow on the roof. The water then refreezes when it reaches the eaves, which tend to be colder than the roof because they hang over the edge. If the ice doesn't fall off the roof, the melting water will continue to build up. Therefore, the trick is to keep heat in and make sure the roof stays cold.

First, check for air leaks into the attic. Gaps and cracks in your insulation around vent stacks or electrical wiring can reduce your insulation's effectiveness by up to 30 percent. Fill gaps with loose fill or expanding foam insulation.