Ice dams are one of the most common and most misunderstood roofing problems in Milwaukee. Every winter, we get calls from homeowners with water coming through their ceilings, not from a roof failure, but from an ice dam that's backed water up under their shingles.
What Actually Causes Ice Dams
Ice dams aren't caused by cold. They're caused by heat loss from your living space warming the roof deck unevenly. Warm air escaping through the attic heats the upper portion of the roof, melting snow. That meltwater runs down to the colder eave overhang (where there's no warm attic below) and refreezes. The ice builds up, traps more meltwater, and that water finds its way through shingle laps and flashings into your home.
The root cause: inadequate attic insulation and/or attic air sealing.
What Doesn't Fix Ice Dams
- Heat cables: treat the symptom, not the cause. They consume electricity indefinitely and fail.
- Removing snow after storms: effective but labor-intensive. Doesn't solve the underlying problem.
- Just replacing the shingles: the new shingles will ice dam too, because the physics haven't changed.
What Does Fix Ice Dams
1. Attic air sealing, blocking the heat pathways from living space to attic (recessed lights, plumbing penetrations, attic hatches)
2. Insulation, minimum R-49 in Milwaukee County attics per current Wisconsin energy code
3. Proper ventilation, continuous soffit-to-ridge ventilation keeps the deck cold uniformly
4. Ice and water shield, required on all Apexium installations, minimum 6 feet from eave, prevents water infiltration even when ice dams form
Emergency Ice Dam Removal
If you have active water intrusion, Apexium offers safe steam-based ice dam removal, the only method that doesn't damage shingles. We don't chop, chip, or use heat guns on shingles.
After removal, schedule an attic inspection. We'll identify the heat loss source and give you options.
No, and this is the most common misunderstanding we deal with. Ice dams are caused by heat escaping into the attic, not by the shingles. New shingles over the same attic will form the same dams the following winter. What a replacement does is let you fix the attic while the deck is open.
They treat the symptom. Cables melt a channel through the ice but run up an electric bill every winter and fail after a few seasons. They are a workaround for a house with a fixable problem, and we would rather spend your money on air sealing.
Steam is the only method that does not damage shingles. Every winter somebody takes a hammer or a garden spade to the eave and puts holes through the roof. If you have active water coming in, call for steam removal rather than chipping.
Current Wisconsin energy code wants about R-49. The catch on low-slope ranch attics is that there is often no room for that depth out at the perimeter without blocking the ventilation channel, and the perimeter is exactly where dams form.
Not on its own. Adding blown insulation without installing baffles blocks the soffit intake and makes ventilation worse, which makes ice dams worse. We have opened attics where a homeowner paid for a top-up and their dams got measurably worse the next winter.
Interior water damage from an ice dam is often covered. The underlying cause, inadequate insulation or ventilation, is a maintenance issue and is not. Carriers vary, so document the damage and check your policy before assuming either way.
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