Causes of Roof Damage in NY
Knowing the specific threats your New York roof faces is the first step in documenting damage, hardening vulnerable areas, and strengthening your position in an insurance claim. Some of the most common causes include the following:
- High-Wind Events: Nor’easters and other windstorms that bring sustained gusts over 50 to 60 mph often sweep through New York, stripping off shingles, lifting flashing, and driving wind-borne debris into roof membranes (NY Hazard Mitigation Report).
- Torrential Rain from Tropical Systems: When hurricanes like Ida dumped over seven inches of rain on the city in a single day, overloaded drains and scuppers forced water under roof seams, saturating the insulation and interior finishes (P-2333 New York City: Effects of Hurricane Ida).
- Heavy Snow, Ice Dams & Freeze-Thaw Cycles: New York receives an average of two feet of snow annually. Repeated freeze-thaw cycles add weight, create ice dams at the eaves, and loosen shingles, opening pathways for leaks when snow melts.
- Ponding Water on Flat Roofs: Many buildings in New York have low-slope or "dead-level" roofs. Clogged drains, settlement, or insufficient pitch can cause water to accumulate for more than 48 hours. This accelerates membrane deterioration and, in extreme cases, can lead to structural deflection or collapse.
- Dislodged Rooftop Equipment: HVAC units, satellite dishes, and solar arrays that are not positively anchored can shift in high winds. Once they skid or topple, sharp edges puncture the membrane, giving rain a direct path into the building envelope.
- Aging Materials & Deferred Maintenance: Flat-roof assemblies approaching or exceeding their 20-to-30-year design life become brittle, and ultraviolet exposure erodes protective surfacing. Small cracks expand into full-scale leaks during the city’s next storm without routine inspections and immediate repairs.