What Causes Ice Dams on Your Roof (and How to Stop Them)
Every Massachusetts winter, you see them. A thick ridge of ice along the edge of the roof, with icicles hanging off the gutters. That ridge is an ice dam, and it is one of the top ways New England roofs leak in the cold months.
How an ice dam forms
It starts with heat. Warm air leaks out of your attic and warms the roof above it. That heat melts the snow on the upper part of the roof. The melt water runs down toward the edge.
The edge of the roof is colder, because there is no warm attic under it. So the water freezes again right there. Do that for a few cold days and the ice builds into a dam.
Why the dam causes a leak
Once the dam is there, new melt water has nowhere to go. It pools up behind the ice and sits on the roof. Then it works its way up under your shingles, where it drips into the attic, the walls, and the ceiling.
So the leak is not really the roof failing. It is ice forcing water somewhere it was never meant to go.
The fix that lasts
You can clear the ice off the roof, and sometimes you have to, fast, before it leaks inside. But that only fixes today's dam. If you do not change anything, the dam comes right back next cold snap.
The real fix is in the attic. Ice dams form because heat leaks out and melts the snow. When you add attic insulation and seal up the heat leaks, the roof stays cold and even. The snow stops melting and refreezing at the edge, so the dam never forms.
This is why we handle roofing and home energy together. We can clear the ice now and fix the cause, instead of you clearing the same dam every January.
What not to do
Please do not climb up and chip at the ice with a hammer or a shovel. It cracks shingles and can hurt the roof more than the ice would. If you have an active ice dam, let someone remove it the safe way.
If ice is building up on your roof, do not wait for it to leak. Learn more about our ice dam removal service and our home insulation work, or email info@MaEnergyAdvisory.com for a free look.
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