If ice dams are forming on your roof, this indicates that warm household air is probably leaking into your attic, or else ductwork is leaking air as it runs through the attic. The best way to deal with an ice dam on your roof – to keep resulting water leaks from ruining insulation and damaging the structure of your attic and home – is to not allow an ice dam to form in the first place. Now that the winter is behind us, you’ll have plenty of time to address this issue before winter hits Kansas City again. Ice dams result from uneven heating on the roof. If heated air is accessing your attic, it will warm up the main part of the roof, melting snow as it lands. This melted snow drips toward the edge of the roof and then refreezes as it hits the much colder roof edge. This ice forms a barrier that causes melted snow to back up behind it, with the pooled water eventually finding its way into your attic, and then the walls and rooms below.
You can prevent ice dams by keeping heat from rising in to the attic. Do the following:
- Identify where air leaks occur. Look for ceiling lights whose fixtures protrude into the attic and seal them from the attic with spray foam or heat-resistant caulk. Make sure the attic hatch or door is properly sealed so air can’t get around the edges.
- Insulate ductwork in the attic. Uninsulated and leaking ducts increase your energy bill and contribute to ice dam formation. Have them tested, sealed and insulated to cut down on thermal losses in the attic.
- Increasing the insulation in the attic. The U.S. Department of Energy recommends that attics in our area have an R-value of 38. The R refers to “resistance” and an R-value of 38 provides 38 hours of thermal protection. Each inch of insulation provides about three hours of protection from thermal transfer, so you’d need approximately 16 inches in the attic. Sometimes the perimeter of the attic has less space for insulation and if that’s the case in your home, use insulating products that have a higher R-value inch-per-inch, such as rigid foam boards or sprayed foam. Insulation on the attic floor should rise to the top of the floor joists.
If you take these steps before our next Kansas City winter, your home will be protected from ice dams. The bonus is that keeping your attic properly sealed and insulated will lower your energy bills year round. Please contact us at Overland Park Heating & Cooling for all of your HVAC needs.
Our goal is to help educate our customers in Overland Park, Kansas about energy and home comfort issues (specific to HVAC systems).
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