The answer to 'asphalt shingles ice dams' is that ice dams are a common problem that can form on the edges of roofs, causing water to back up and potentially leak into the home. This is often caused by poor insulation and ventilation in the attic, which allows heat to escape and melt snow on the roof, only for it to refreeze at the colder roof edges.
Symptoms of ice dams include icicles forming along the roof's edge, water stains or damage on the interior ceilings and walls, and ice buildup that prevents proper drainage. Solutions can include improving attic insulation and ventilation, removing snow from the roof, and installing heat cables or de-icing systems to prevent ice dam formation. In some cases, it may be necessary to call a professional roofing contractor to properly address the issue.