Ice dams are one of the most common and damaging winter roofing problems in New York — particularly in Westchester, the Hudson Valley, the Capital Region, and Upstate NY where freeze-thaw cycles are severe.
How ice dams form: Heat escaping from inadequately insulated attics melts snow on the upper roof. The meltwater flows down and refreezes at the cold eaves, creating a dam of ice that forces water under shingles and into the home, damaging ceilings, walls, and insulation.
Ice dam prevention — the right way:
- Attic insulation: R-49+ is the building code minimum for NY — many older homes are severely under-insulated
- Attic ventilation: Balanced intake at soffits + exhaust at ridge keeps the roof deck cold and uniform
- Ice-and-water shield: Applied at eaves during roofing replacement — NY code requires minimum 24 inches; quality NY roofers apply 36–48 inches or full coverage in high-risk zones
- Roof pitch: Steeper pitches shed snow faster and reduce ice dam formation
Emergency ice dam removal: Steam removal by a licensed contractor is the safest method — avoid ice melt chemicals (damage shingles and gutters) and chopping (damages roofing materials). Emergency removal: $500–$1,500 depending on size.
If you're replacing your roof after ice dam damage, address all three factors — insulation, ventilation, and ice-and-water shield — to prevent recurrence.