By the SSKM Construction team · Last updated: August 7, 2026
Every winter, after the first real snow that sticks and then a cold snap, the calls start. Water shows up on a bedroom ceiling, or drips behind the gutter, and the roof was fine in October. Nine times out of ten the cause is an ice dam, and it is one of the most common reasons a sound roof leaks in the Hudson Valley. Understanding why it happens is the difference between fixing it once and fighting it every January.
How an ice dam actually forms
Start with snow sitting on the roof and an attic that is warmer than it should be. Heat leaking up from the living space warms the underside of the roof deck near the ridge, and the snow there begins to melt even while the air outside stays below freezing. That meltwater trickles down the slope until it reaches the eave and the roof overhang, which hang out past the warm walls and stay cold. There the water refreezes, and a ridge of ice builds along the edge of the roof.
Once that ridge is there, the next round of meltwater has nowhere to go. It pools behind the ice, and standing water on a shingle roof does what shingles were never designed to stop: it works uphill under the shingle courses, past the underlayment on an older roof, through the deck, and into the attic or the wall. The icicles hanging off the gutter are the pretty version. The damage is happening above them, out of sight.
Why Hudson Valley homes are prone to it
Our winters supply exactly the conditions an ice dam needs. We get real snow that lingers, long stretches below freezing, and the daily thaw and refreeze that keeps the melt-and-freeze cycle running for weeks. Older housing stock is a factor too. Many of the homes we work on in Newburgh, Poughkeepsie, and the river towns were built before attic insulation and roof ventilation were understood the way they are now, so heat escapes into the attic freely and the roof cannot shed it.
Complex roof lines make it worse. Valleys, dormers, and low-slope sections over additions all create cold pockets and drainage choke points where ice builds first. If your home has had a recurring leak in the same corner every winter, the roof geometry there is very likely part of the story.
The fixes that last, and the ones that do not
Chipping the ice off, raking the roof, and running heat cables all treat the symptom. They can protect the house in an active emergency, and there are winters where you do what you must to stop water coming in. But none of them address why the snow is melting unevenly in the first place, so the dam comes back with the next storm.
The durable fixes work on the attic, not the ice. The first is air sealing and insulation: stopping warm household air from reaching the attic keeps the roof deck cold and even, so snow does not melt from below. The second is ventilation, a balanced path for cold outside air to move from the soffits up to a ridge vent, which flushes out any heat that does get through and keeps the whole roof close to outdoor temperature. On the roof itself, a proper ice-and-water shield membrane along the eaves is the last line of defense, sealing around fasteners so that if a dam does form, water still cannot get through the deck. We build that membrane in as standard on any roof replacement we do.
If a dam has already caused a leak
Get the interior damage documented and the source found. An ice-dam leak often shows up several feet from where the water actually entered, because it travels along the framing before it drips, so tracing it back matters. We handle that kind of roof repair through the winter, and when we are up there we look in the attic as well, because fixing the shingle without addressing the ventilation just sets up next year's leak. Homeowners in Newburgh and the surrounding towns can call us to look at a recurring winter leak and tell you whether it is a roofing fix, an insulation fix, or both.
Frequently asked questions
Will cleaning my gutters stop ice dams?
Clean gutters help water drain in the shoulder seasons, but they do not stop an ice dam. The dam forms from snow melting on the roof and refreezing at the cold eave, which happens whether the gutter is clear or not. The fix is keeping the roof deck cold with insulation and ventilation.
Are ice dams covered by homeowners insurance?
Sudden interior water damage from an ice dam is often covered, though policies vary and long-term neglect usually is not. Document the damage and check your policy. Our guide to filing a roof insurance claim in New York covers the steps.
Can you fix an ice dam leak in the middle of winter?
Yes. We stop the active leak and trace it to its source, then plan the ventilation or insulation work that keeps it from returning. We do not fabricate urgency, but an active leak is treated as urgent because water sitting in a roof assembly gets more expensive by the day.