Preventing Ice Dams on Your CT Roof
‘Tis The Season For Those *#@! Ice Dams!
How to prevent the home-damaging, scourge of wintertime….and make your home more comfortable in the process.
It may not be cold out now, but it is never too early to think about that wintertime problem: ice dams. Ice dams are a problem that can have a structural, cosmetic and financial effect on your home. Right now is the perfect time to start incorporating solutions that can prevent this roofing dilemma. Ice dams are caused when snow melts and refreezes.
Ice dams can occur when there is the combination of just two things:
• snow
• a pitched roof
During the heating season, warm air from inside your house rises naturally by convection. When some of this air escapes into your attic, it warms the roof –especially upper sections of the roof where the warmest air collects. The snow on the roof melts and runs down the roof to the eaves or overhangs. That section of the roof is colder, since it’s not heated by the warmth of the house. The water then freezes. As this melting and freezing cycle repeats, a ridge or dam is formed along the edge of the roof, holding back the continuing run-off. This reservoir of water can work its way under your roof shingles and into your home, damaging insulation, drywall, flooring and other materials. Ice dams are fairly common and the solutions to them are two preventative measures; insulation and ventilation.
Sealing air leaks & upping R-Value
Rising heat from your house is the first step in the formation of ice dams. So, keeping that heat in your home is essential to prevent ice dams. As a bonus, these preventative measures will also keep your house warm and cozy, while cutting your heating expenses as well!). To prevent heat loss into the attic, have your attic professionally air-sealed to cut down the volume of warm air that leaks into the attic from below. The energy technicians will use spray foam, caulk and other products to seal gaps, cracks and openings that admit air into the attic space. Then you can upgrade your attic insulation to the higher levels recommended by the U.S. Dept. of Energy.
Also, install weather stripping or insulation lining around attic entrances, stairwells and stairway entrances, ceiling fan and lighting fixtures, hatches, and anything that is mounted above your ceiling. These “holes” are an easy escape route for heat and need to be blocked.
Improving attic ventilation to keep the roof cold
If your roof surface is cold, snow won’t melt to start the ice dam cycle. You’ve already taken one important step to keep the roof cold: reducing air leakage and increasing attic insulation. Now for step 2: improving attic ventilation. Good attic ventilation allows a steady supply of cold exterior air to be drawn into the attic space (above your insulation, of course) as warmer air exits the attic through ridge or gable vents, This “wash” of cold air helps to keep the roof cold. Attic ventilation is typically achieved with a combination of soffit vents (installed in the soffit that runs along the eaves), gable vents (installed in the gable ends) and ridge vents (installed along the peak of the roof).
The most reliable recommendation for proper attic ventilation is 1 square foot of venting for every 150 square feet of attic flooring. According to these numbers, there are many homes are not adequately ventilated. Consult with a home energy expert or an experienced roofing contractor to determine if your roof vents need to be enlarged or improved to achieve effective attic ventilation.
