How to Remove an Ice Dam Safely (and What Not to Do)
The safest way to remove an ice dam is to pull snow off the lower roof with a roof rake from the ground, then melt a drainage channel with calcium chloride ice melt packed in a nylon stocking. For heavy dams or anything you cannot reach safely, hire a pro who uses steam. Never chip at the ice with a hammer, shovel, or chisel, because you can tear up shingles and get hurt.
Reviewed by the Three Rivers Contracting project team · MN Residential Building Contractor BC760638
Ice dam removal: what works
An ice dam is a ridge of ice at the roof edge that traps meltwater behind it. Removal is a short-term fix. It stops water from backing up under the shingles while you work on the real cause, which is heat leaking into the attic. Three methods are widely recommended.
1. Rake the snow off the lower roof
Use a long-handled aluminum roof rake from the ground. This Old House suggests starting with the bottom 1 to 2 feet of snow and working up in sections, and standing back from the eaves because snow can slide in a mini avalanche. Travelers suggests pulling snow back about 3 to 4 feet from the lower edge, taking care not to damage the roof covering. Removing snow before it melts and refreezes keeps a dam from growing. A rake costs roughly $50 to $200, according to Angi.
2. Calcium chloride in a stocking
Fill a nylon stocking or pantyhose leg with calcium chloride ice melt and lay it vertically across the dam so it overhangs the gutter or eave. It melts a channel that lets trapped water drain. Cover shrubs below, since runoff can harm plants.
3. Cool the leak from the attic
If water is already coming in, a box fan aimed at the wet spot in the attic can freeze the water in place and slow the leak. This is a stopgap while you arrange real repairs.
What not to do
| Method | Why to avoid it |
|---|---|
| Hammer, chisel, shovel, or pick | Can gouge shingles, loosen granules, and cause falls; damage may not be covered by insurance |
| Rock salt (sodium chloride) | Can damage roofing, plantings, and metal; calcium chloride is the recommended product |
| Torches or open flame | Fire hazard and roof damage |
| Hot water from a hose | Melts slowly, refreezes, and can flood walls and worsen interior leaks |
| Ladder on an icy roof edge | High fall risk in snowy or icy conditions |
Angi warns against contractors who use hammers or blowtorches, and notes that damage from those methods may not be covered by homeowners insurance. Ask any company how they remove ice before you hire them.
When to call a pro
Call a professional if the dam is thick, if you cannot reach it from the ground, if the roof is steep, or if water is already inside the house. Angi calls steam a much better option than hacking at ice, but it needs the right equipment. Pricing varies by size and access, so get a quote. Act quickly if you see water stains on ceilings or along exterior walls, because moisture may already be under the roof membrane. See our roof installation and repair services for repair help afterward.
Twin Cities timing: why dams form when they do
In the Twin Cities, dams usually build after a snowfall followed by cold, then a stretch of sun or milder days, and then a hard freeze. The roof deck above heated space warms enough to melt snow, and the eave stays cold. Water refreezes there and builds up layer by layer. A thaw-and-freeze week in January or February is the classic setup. Watch the forecast after a big snowfall, and rake before the temperature swing, not after.
Protecting the inside of your house
- Check ceilings and the tops of exterior walls for stains, bubbling paint, or drips.
- Look in the attic for wet insulation, frost on the roof deck, or damp rafters.
- Move belongings, place buckets, and protect floors under any active leak.
- Photograph any damage right away for your insurer.
- Dry wet insulation and drywall quickly. Moisture can lead to mold growth.
The permanent fix
Removal treats the symptom. The cure is keeping the roof deck cold: air seal the attic floor, add insulation, and make sure the attic is ventilated. Eaves with ice and water shield add backup protection. We explain the cause in why ice dams form and how to stop them, and our ice dam prevention page covers what we do. For insulation targets, see attic insulation R-values and rebates.
Heat cables and heated gutters can help in problem spots. Angi lists heat cables at about $500 to $1,300 depending on roof size, and heated gutters at roughly $13 to $26 per linear foot installed. Treat those as a patch for a roof that cannot be fixed another way, not a replacement for insulation and ventilation.
Want a straight answer on your own house? Call (651) 565-1349 or get a free estimate from Three Rivers Contracting.
Frequently asked questions
What is the safest way to remove an ice dam?
Use a roof rake from the ground to clear snow from the lower roof, then lay a stocking filled with calcium chloride across the dam to melt a drainage channel. If the dam is thick or unreachable, hire a pro who uses steam. Avoid ladders on icy surfaces.
Can I use rock salt to melt an ice dam?
No. Rock salt (sodium chloride) can damage roofing and harm plants and metal near the downspouts. Calcium chloride is the product commonly recommended for ice dam channels, and it should be used in a stocking, not scattered across the roof.
Is it okay to chip an ice dam off with a hammer?
No. Hammers, chisels, and shovels can tear shingles, loosen granules, and cause falls. The damage may also not be covered by homeowners insurance. If the ice is too thick to treat safely, hire a professional who uses steam instead of striking the roof.
Will removing the ice dam stop future ice dams?
Not by itself. Removal only handles the current dam. New dams will form until you fix the cause, which is warm air leaking into the attic. Air sealing, more insulation, and attic ventilation keep the roof deck cold and prevent meltwater from refreezing at the eave.
When should I call a professional?
Call if the dam is large, the roof is steep, you cannot safely reach it from the ground, or water is already getting inside. Pros use steam, which melts ice without striking the roof. Get a written quote and ask what method they use.