The answer to 'asphalt shingles ice dams' is that ice dams can form on asphalt shingle roofs due to poor insulation, ventilation, or drainage. Ice dams occur when heat escapes through the roof, causing snow to melt and then refreeze at the roof's edge, creating a barrier that traps water and leads to leaks and damage.
Symptoms of ice dams include icicles forming along the roof's edge, water stains or mold on interior walls and ceilings, and damaged or missing shingles. Solutions include improving attic insulation, adding roof vents, and installing heat cables or de-icing systems. In severe cases, it may be necessary to have a professional remove the ice dam and make repairs to the roof and interior.