During snow and ice season, ice dams are an invisible threat that can cause major damage to your home and roof. Learn how you can help to keep them from forming.
It was the middle of winter and everybody had snow-covered roofs, so I had no idea what was happening,” says Martha Shay, a homeowner in Pottsville, Pennsylvania.
When she spotted a small, wet area on her ceiling, it didn’t take long to trace the dripping water back to the source: a massive ice dam had formed under shingles on her roof and inside a gutter. Heat escaping from ducts and other areas in her attic had caused a cycle of snow on the roof melting and refreezing. The melting snow eventually backed up behind the ice dam and worked its way under the roof and into the house. “It was a big mess.”
The final bill to fix the damage: more than $4,000.
Ice dams are typically caused by poor insulation and lack of adequate ventilation in attic spaces, says Joe Palumbo, president of The Ice Dam Guys in Minneapolis, Minnesota. Damage from an ice dam can sometimes cost tens of thousands of dollars to fix, he says. “We’ve seen entire ceilings fall to the floor.”
A homeowner’s best defense against ice dams, according to Palumbo: a home energy audit with a blower door test—which can cost $200 to $650, depending on the service and your location. The blower door, a machine used to measure a home’s airtightness, can also be used to locate air leaks in a home. “If everybody got this test, it would put us out of business.”
According to the U.S. Department of Energy, a state or local government energy office can help you find a company or organization to perform an energy audit. Some local utility companies offer free energy audits, but these audits may not include the imaging or testing equipment used by professional auditors. If you’re considering an energy audit, ask specific questions, such as “Do you use a blower door?” to find out if the auditor provides the assessments you need.