Ice dams on the roof can cause issues like roof leaks, mold, and it can also drain your bank account. But, stopping ice dams reallyis simple. Just keep the entire roof the same temperature as the eaves. See, I told you it was simple. 
OK, ok you do that by increasing ventilation, adding insulation, and sealing off every possible air leak that might warm the underside of the roof. By taking following these steps you should enjoy a winter free of dams and use less energy to boot.
1. Ventilate Eaves and Ridge
A ridge vent paired with continuous soffit vents circulates cold air under the entire roof. Both ridge and soffit vents should have the same size openings and provide at least 1 square foot of opening for every 300 square feet of attic floor. Place baffles at the eaves to maintain a clear path for the airflow from the soffit vents.
2. Cap the Attic Access Hatch
An unsealed attic hatch or whole-house fan is a massive opening for heat to escape. Cover them with weatherstripped caps made from foil-faced foam board held together with aluminum tape.
3. Exhaust to the Outside
Make sure that the ducts connected to the kitchen, bathroom, and dryer vents all lead outdoors through either the roof or walls, but never through the soffit (it kinda defeats the purpose).
4. Add Insulation
More insulation on the attic floor keeps the heat where it belongs. To find how much insulation your attic needs, check with your local Home Store or building department.
5. Install Sealed Can Lights
Old-style recessed lights give off great amounts of heat and can’t be insulated without creating a fire hazard. Replace them with sealed “IC” fixtures, which can be covered with insulation.
6. Flash Around Chimneys
Make sure the gap between chimney and house framing have L-shaped steel flashing held in place with unbroken beads of a fire-stop sealant. Using canned spray foam or insulation isn’t fire safe.
7. Seal and Insulate Ducts
Spread fiber-reinforced mastic on the joints of HVAC ducts and exhaust ducts. Cover them entirely with R-5 or R-6 foil-faced fiberglass. Seal around electrical cables and vent pipes with a fire-stop sealant. Also, look for any spots where light shines up from below or the insulation is stained black by the dirt from passing air.
Following these simple steps can keep those pesky ice cycles where they belong….on your neighbors house.
To have your Home Inspected, by Licensed Inspector Kevin Michaels, and get an easy to read and understand report on the condition of your roof or attic, call Hudson Valley Property Inspections @ 845-399-3983. Or click on Contact