Ice Dams in Minnetonka: Why Some Homes Keep Getting Them

Some Minnetonka homes get ice dams winter after winter while their neighbors do not. It is rarely bad luck — it is almost always attic bypass and ventilation, and it is fixable once you understand the mechanism.

How an ice dam forms

Warm air leaking from the living space into the attic warms the roof deck. Snow melts on the warm upper roof, runs down to the cold eaves and overhangs, and refreezes — building a dam of ice that backs meltwater up under the shingles or shake and into the walls and ceilings.

Steep architectural shake roofs and complex valleys, both common here, concentrate the problem on north-facing planes.

The real fix

Heat cables and roof raking treat the symptom. The cure is air-sealing the attic bypasses and balancing intake and exhaust ventilation so the roof deck stays cold. We map insulation depth, air leakage, and ventilation on every inspection and flag the interior staining that reveals past dams.

See the ice dams defect page and our roof and attic system page for the details we check.

Keep reading

Learning center · Defect library · Full home inspection