Ice Dams in Minneapolis Homes

Ice dams in Minneapolis are usually caused by warm, moist air leaking from the house into the attic, which melts roof snow that then refreezes at the cold eaves. In the short term, clear snow from the ground and get help with active leaks. The lasting fix is sealing attic air leaks, then adding insulation.

Why are ice dams so common in Minneapolis?

Because Minneapolis has a long, cold winter with a lot of snow sitting on roofs. Based on NOAA's 1991–2020 climate normals for Minneapolis–St. Paul International Airport (NOAA climate normals, MSP Airport):

• Snowfall averages 51.2 inches a season. The Minnesota DNR notes this is 4.5 inches more than the 120-year long-term average (Minnesota DNR).
• About 147 nights a year drop to freezing or below, and about 72 days never get above freezing.
• January's normal high is 23.6°F and its normal low is 8.8°F (NOAA monthly normals, MSP Airport).

Some winters are far snowier than normal. The DNR's records list 1983–84 as the Twin Cities' snowiest season, at 98.6 inches (Minnesota DNR).

Put together, that means snow can sit on a roof for weeks while outdoor temperatures stay well below freezing. Any heat leaking into the attic has plenty of time to melt snow from below, and the cold eaves have plenty of time to refreeze it.

How does an ice dam form?

The University of Minnesota Extension describes the process simply. Heat reaches the roof, mostly through air leaks from the house into the attic. Snow on the warm part of the roof melts. When that water runs down and reaches roof edges that are below 32°F, it freezes. The ice builds into a ridge, and more meltwater pools behind it (University of Minnesota Extension).

Pooled water can back up under shingles and into the house. Extension says it can damage walls, ceilings and insulation, stain ceiling finishes, and lead to mold and mildew.

The Minnesota Department of Commerce puts it even more directly: "The primary cause of ice dams is attic air leaks" (Minnesota Department of Commerce). Warm, moist air escaping around plumbing vents, wiring and chimneys can also condense and freeze in the insulation, soaking it so it insulates poorly.

What makes a house more likely to get ice dams?

Extension lists features that raise the risk (University of Minnesota Extension):

• Recessed lights in top-floor ceilings.
• Skylights.
• Complex roof designs with valleys and dormers.
• Heating ducts in the attic, especially leaky ones.
• Chimneys, and frequent use of a wood stove or fireplace.
• Exhaust vents that end just above the roof, especially in heavy snow areas.
• Leaky ceilings, including gaps around light fixtures and other openings.

Having one of these features doesn't mean your house has a problem. But if you see icicles and ice ridges forming at the same spots every winter, the attic area right above them is a good place for a pro to start looking.

When are ice dams most likely in Minneapolis?

Usually from December through March, and especially after a big snowfall followed by a stretch of cold. NOAA's monthly normals for the airport show snow arriving in November (6.8 inches on average) and peaking in December (11.4 inches) and January (11.0 inches), with February at 9.5 inches and March still at 8.2 inches (NOAA monthly normals, MSP Airport).

Late winter can be tricky. In March, the normal high is 41.7°F and the normal low is 24.9°F, so snow on the roof can melt in the afternoon sun and refreeze at the eaves overnight. That's on top of melting caused by attic heat.

A few practical points:

• Watch after heavy snows. More snow on the roof means more meltwater when attic heat or sun goes to work on it.
• Watch during long cold snaps. The colder it is outside, the bigger the difference between a warm roof deck and frozen eaves.
• Keep watching into March. Spring snow and freeze-thaw cycles can keep dams forming.

What are the signs of an ice dam problem?

Look from the ground and from inside. Don't climb a ladder or go onto an icy roof.

• A thick ridge of ice along the eaves, often with large icicles.
• Icicles or ice coming from behind the gutters or out of the soffits.
• Water stains or wet spots on ceilings or the tops of exterior walls, especially near the eaves.
• Peeling paint or bubbling on ceilings or exterior walls near the roof edge.
• Frost or wet insulation in the attic, if you can look from the attic hatch safely.
• Uneven snow on the roof, with bare patches over warm spots and heavy snow at the edges.

If water is dripping near a ceiling light, fan or outlet, stay away from that spot. Turn off the circuit at the breaker only if you can do it without standing in water, and call for help.

What can you do right now about an ice dam?

Focus on removing snow safely from the ground and getting water under control inside.

• Rake the lower part of the roof from the ground. This Old House recommends a long-handled roof rake used from the ground, focusing on the first 3 to 4 feet up from the eaves (This Old House). Extension notes that raking removes one ingredient an ice dam needs, but warns a rake "may damage the roofing materials" (University of Minnesota Extension). Go gently and keep the blade off the shingles.
• Stay off the roof and ladders. Extension warns that anyone on the roof in winter, or working on the roof from below, risks injury. This Old House advises leaving areas you can't reach from the ground to a professional.
• Catch and contain water inside. Move belongings, set out buckets and towels, and photograph the damage for your insurer.
• Call a pro for removal. Ice dam removal is a job for a crew with the right equipment.

What not to do, according to the Minnesota Department of Commerce (Minnesota Department of Commerce):

• Don't chip at the ice or use chemicals or heat on it. These can damage shingles, gutters and other parts of the house.
• Don't count on heating cables. Commerce says they shorten the life of your roof and cost money to run. This Old House calls them "really just a Band-Aid."
• Don't add roof vents, including powered vents, to fix the problem. Commerce says they won't eliminate ice dams and often make the problem worse.

For a broader explanation of how ice dams work anywhere in the country, see ice dams explained.

How do you prevent ice dams for good?

Stop the heat from reaching the roof. Extension's long-term advice is in this order (University of Minnesota Extension):

1. Make the ceiling airtight first, so no warm, moist air flows from the house into the attic. Typical leak points are recessed lights, plumbing vents, wiring holes, chimney chases, the attic hatch and the tops of walls.
2. Then add ceiling or roof insulation to cut heat loss by conduction.
3. Keep ventilation modest. Extension says only small amounts of roof ventilation are needed once the first two steps are done well, and it does not recommend mechanical attic ventilation.

The Minnesota Department of Commerce says foam spray or caulking can seal these air leaks, "saving energy and preventing nearly all ice dams" (Minnesota Department of Commerce). Its guide also notes that insulation alone is insufficient if the air leaks remain.

Is there help for air sealing in Minneapolis?

Yes. Home Energy Squad is an in-home energy visit provided by CenterPoint Energy and Xcel Energy and delivered by the nonprofit Center for Energy and Environment. It's available to Minnesota residents with a CenterPoint Energy or Xcel Energy account (Center for Energy and Environment). According to the program:

• Visits include an insulation inspection of the attic and walls.
• The visit for homes built before 2000 includes measuring air leaks with tools like a blower door.
• Crews install materials such as door and attic hatch weather-stripping.
• Income-qualified households may get a free visit, and some cities reduce or cover visit costs.

An energy visit can show you where the air leaks are before you hire anyone for insulation or roofing work.

What does ice dam repair cost?

It depends on whether you need removal only, or also roof, ceiling and insulation repairs. These are national figures, not Minneapolis prices, as of 2026:

• Ice dam removal: Fixr says removing an ice dam falls between $400 and $1,500 (Fixr).
• Replacing damaged or missing shingles: typically $150 to $700 (Fixr).
• Flashing repair: usually $200 to $600 (Fixr).
• Gutter repair: clogged gutters cost between $100 and $250 to unclog and repair (Fixr).
• Roof inspection: most homeowners pay between $307 and $571 (Fixr).

Interior repairs such as drywall, paint and wet insulation are separate. For more on leak repairs, see our roof leak repair cost guide.

What does Minnesota code require when you reroof?

The 2020 Minnesota Residential Code applies statewide. Saint Paul's reroofing guideline, which applies that code, says an ice barrier must replace normal underlayment and run from the lowest edges of all roof surfaces to a point at least 24 inches inside the exterior wall line (City of Saint Paul). That membrane helps keep backed-up meltwater out of the house, but it does not stop an ice dam from forming. Only cutting heat loss into the attic does that.

Other points from the same guideline worth asking about:

• Venting must meet current code when a sloped roof is torn off, though a full insulation upgrade isn't required on a sloped roof.
• Overlays need prior approval from the building inspector.
• Gaps in old board decking wider than 5/8 inch must be filled or covered.

Who can pull a roofing permit in Minneapolis?

Minneapolis says contractors who apply for a building permit must show proof of a residential specialty contractor license or a state license, such as a Residential Roofer license. Owner-occupants can also apply for a permit to do their own work (City of Minneapolis).

The Minnesota Department of Labor and Industry licenses residential roofing companies. Its license page lists a $15,000 surety bond and liability insurance of at least $300,000 per occurrence among the requirements (Minnesota Department of Labor and Industry). You can look up a company's license through the department's "Check a License" tool.

What should you ask a roofer or insulation company?

1. What is your Minnesota license number, and will you pull the permit?
2. Where do you think the heat is getting into the attic, and how will you seal it?
3. Will you check for wet insulation and ceiling damage, not just the roof?
4. How will you remove the ice without damaging shingles and gutters?
5. Does the reroof quote include the ice barrier 24 inches inside the wall line?
6. How will you handle recessed lights, bath fans and the attic hatch?
7. What does your warranty cover?

If water got into the house, our guide to roof damage insurance claims explains how to document it.

When should you call a pro?

Call right away if water is coming inside, if ice is pulling gutters loose, or if you see the same ice ridge returning after every snow. Plan an attic air-sealing check in fall, before snow arrives. Stay off the roof in winter.

Bellwick is a free service that helps you understand the likely problem and can connect you with a local company. Bellwick doesn't do the work. If you want a quick read on what you're seeing, check my roof.