What Is An Ice Dam?
Ice dams are humps of ice that form when the heat from the inside of a home escapes into the roof and warms the roof decking under certain wintertime conditions. This heat, along with the heat from the sun, can melt the underside of the layer of snow on the roof. The water will trickled down towards the eaves between the layer of snow and the shingles. This part of the roof stays cold because it extends beyond the side of the house, causing the water to refreeze. This continual thaw and freeze process is what creates an ice dam. The ice dam forces the water back up under shingles and behind fascia. Ultimately, it can soak through the roof deck and cause damage to attics, ceilings and walls by dripping into the insulation and ruining sheet rock and paint. If the ice dam breaks free, it can pull shingles and gutters off also, damaging anything it falls on. If the area under the shingle stays wet, it can form mildew and start to rot.
The flatter the pitch of the roof, the easier it is for an ice dam to get a grip, because gutters at the eves are more likely to trap snow and ice.
HOW TO PREVENT AN ICE DAM?
Proper insulation and ventilation help prevent ice dams. Homes can lose up to 40% of their heat through an uninsulated attic. Newer homes have high standards of insulation, but older homes build before the 90’s usually need more insulation. Ventilation keeps rising heat and moisture in the air moving out of the attic, preventing rot and ice dams.
You can also replace your shingle roof with standing seam or other metal roof. Or you can replace the bottom three feet or so of your shingle roof with a wide metal drip edge. Regardless, you should make sure a water-repellant membrane is installed under any new roofing.
NOTE: If your roof is not very steep, an ice dam can still form on metal roofing and drip edges.
As a local business, we understand the weather in Bend and the rest of Central Oregon. Our attention to detail and quality materials will ensure that your roof is properly insulated and ventilated to withstand our snow, ice and hail storms without forming an ice bank.
In the middle of winter when roads are treacherous and the problem is immediate, is not the best time to make sure your home is protected. Summer is the best time to maintain your home. Have an honest, experienced roofer perform a maintenance visit. They will examine your roof and attic to make sure that everything is properly installed and that your roof will be weather proof and water proof this upcoming winter.