The answer to 'shingles ice dam' is that an ice dam is a buildup of ice along the eaves of a roof that can cause water to back up under the shingles and leak into the home. Common causes include poor attic insulation, inadequate ventilation, and heavy snow accumulation. Symptoms include icicles forming along the roof edge, water stains on interior walls and ceilings, and shingles lifting or falling off.
The best solution is to prevent ice dams from forming in the first place by improving attic insulation and ventilation. This may require hiring a professional roofer or insulation contractor. If an ice dam has already formed, you can try melting it with calcium chloride ice melt products, but this is only a temporary fix. For severe ice dams, it's best to call a professional roofer to safely remove the ice and inspect for any underlying roof damage.