When ice dams form on a roof homeowners have very few safe options to remove it themselves. Many try to chop at the ice with hammers or axes but mechanical methods almost always result in roof damage. Over the years we’ve seen hundreds of roofs scarred by well-intentioned people trying to remove ice dams with tools never meant for the job. The most common forms of damage are cuts, bruises and perforations of the roofing material and holes punched in valley metal.
It is always less expensive to prevent ice dams than to remove them or to repair the damage they leave behind. Once an ice dam has developed, removal is labor-intensive and costly. Ignoring prevention also means the same ice dam can reform multiple times in the same season. Leading experts like The Ice Dam Company in Minneapolis report revisiting the same properties multiple times in one winter to remove ice dams from the same location.
Ice dams are not caused by snow alone. They form when the right combination of snow and temperature creates meltwater that refreezes at the roof edge. The “sweet spot” is nighttime lows around 15°F and daytime highs around 25°F. At these temperatures, roof heat loss is enough to cause melting, but the eaves are still cold enough to freeze water.
Illustration courtesy of Kuhl’s Contracting Inc.
Don’t be fooled. Just because you have icicles hanging off your roof doesn’t mean you necessarily have ice dams. Outside of water leaking inside your home, here are six warning signs to look for:
Illustration courtesy of The Ice Dam Company
Ice dams typically form on eaves—the lower part of the roof above exterior walls—but they can also form around vents, valleys, skylights, and chimneys. Here’s where they most commonly appear:
Illustration courtesy of The Ice Dam Company
The only proven, safe method for removing ice dams is with high-temperature steam. Steamers cut through ice without damaging shingles. Many contractors claim to use steam when they’re actually using hot water pressure washers—if the wand has a trigger, it’s not a steamer.
The most efficient and ethical method to remove an ice dam is to cut 16-inch channels through the ice and undercut between the slots using steam. This breaks the ice into manageable sections without damaging roofing materials.
Photo courtesy of Kuhl’s Contracting Inc.
Professional ice dam removal is expensive because it requires specialized equipment. Steamers cost $5,000 or more and they’re easy to damage if you don’t know exactly what you’re doing. This is why you won’t find ice dam steaming equipment in rental shops. Most contractors charge by the hour, anywhere from $400 to $800 for a one- or two-person crew. Other factors that play a role in how much it costs to have an ice dam removed include the height of the work, the thickness and length of the ice dam, and how cold it is outside.
If water is already entering your home through the ceiling, the best emergency step is to punch a small hole in the ceiling and place a bucket below. This prevents water from spreading across ceilings, leaking through light fixtures and causing hidden damage.
Looking for a good resource for everything ice dams? The Ice Dam Company, founded in Minneapolis in 2003, was the first large-scale ice dam removal and prevention company in the United States. Thousands of projects later, they continue to set the standard. Their sister company, Kuhl’s Contracting, also provides extensive resources on removal, prevention and heat cable installation.
