| Article courtesy of State Farm Insurance|
Ice Dams And Attic CondensationFeb 14, 2011
By Staff writer State Farm™ Employee
While stopping a leak or repairing a hose down in the basement might be fairly straightforward, ice dams and attic condensation, two forms of water damage typical to cold climate homes, are a little more complicated and a little trickier to fix. And since many homeowners aren't frequent visitors to their own attics in the frigid winter months, water damage on the top floor might catch you off guard.
What are ice dams? What causes attic condensation? And if you’ve got either, what can you do?
When the temperature in your attic is above freezing, snow on the roof will likely melt. When the snowmelt runs down the roof and hits the colder eaves, it refreezes, especially if the temperature drops again.
If this cycle repeats over several days, the freezing snowmelt builds up and forms a dam of ice, behind which water pools up into large puddles, or "ponds". The ponding water can then back up under the roof covering and leak into the attic or along exterior walls.
right weather conditions for ice dams are usually when outside air
temperatures are in the low 20s (°F) for several days with several
inches of snow on the roof.
Condensation of water vapor on cold surfaces in attics can cause wood to rot, which can lead to costly repairs. Condensation typically occurs when warm, moist air migrates into the attic from living spaces below. Research indicates unusually high humidity in the home's living spaces is strongly associated with attic condensation problems.
Building codes have some requirements that attempt to prevent the problems of ice dams and attic condensation. But codes don’t address all the issues, and many houses are built without following building codes. First and foremost, it’s your builder or designer's job to understand the relationship of humidity and air movement when designing and constructing the house so these problems don't occur.
Nevertheless, there's more you can do. Here are a few simple steps that can help prevent ice dams and condensation in your attic:
What Not To Do
While it might be tempting to try a quick-fix to break up that ice dam, don’t get too eager; not only is it dangerous on your roof, but you can also cause a lot of damage, especially in the colder months. Here are some things to keep in mind: