Si desea leer este artículo en español visite El Planeta.
Wintery weather across Massachusetts over the last couple weeks has brought a resurgence of a dreaded and damaging problem not widely seen in recent years: ice dams.
Many homeowners are finding moisture creeping into their homes, potentially leading to expensive damage.
“We are seeing an increase in the number of ice dam-related claims, and one of the reasons why we’re seeing a number that is increasing is because for the first time in several years, we’re actually having a winter here in Massachusetts,” said Frank O’Brien of the Massachusetts Property Insurance Underwriting Association. “It’s cold and there’s a lot of snow, which are two things needed for the formation of an ice dam.”
That’s made it a busy time for building contractors too.
Rob Robillard, a remodeling contractor who runs a company called Concord Carpenter, said the phone now rings every day with people facing ice dams.
“In the last two weeks I’ve had 26 calls and about 15 or 20 emails asking for ice dam removal,” Robillard said. “I want to say the last time we had a big, big call out like this, I think was 2015, maybe.”
Indeed, ice dams are nothing new in New England. The winter of 2015 had similar conditions — significant snowfall followed by an extended period of frigid temperatures. But that year was worse, said GBH meteorologist Dave Epstein.
“We had almost the entire month of February that year below freezing. And we didn’t go above 40 until early March,” Epstein said.
While not quite as bad as 2015, this winter has been no joke. Nearly two feet of snow fell in Boston in late January, followed by consistently low temperatures.
“This is a formidable cold. It’s more typical,” Epstein said.
And we’ve gotten out of the habit of expecting this.
“We just had really mild winters, the past several,” Epstein said.
Ice dams happen when the snow on a roof starts melting.
“The main cause of ice dams, besides the fact you have two feet of snow, is lack of insulation,” said Mark Philben, who works with Charlie Allen Renovations in Cambridge.
Heat rising through poorly insulated roofs melt the snow, and that water runs down until it reaches the cold overhang and turns solid again. Over time, that creates a “dam” of ice that holds back water from getting off the roof.
“You’ve just got this dam of ice at the edge of your roof and now the melting water can’t get anywhere, and it backs up underneath your shingles and gets into your house and down your walls and your ceiling,” Philben said.
That can lead to significant damage.
“Probably the worst thing that it causes is mold, if it’s left unchecked,” Robillard said. “I tell people, you get one ice dam, don’t worry about ripping the walls open, but if you’ve had ice dams continually for several years, you’re probably going to have mold in those walls. It can damage plaster, paint, woodwork. It can cause all kinds of problems. It can get into electrical.”
The best way to prevent ice dams from happening is to ensure that your home is sufficiently insulated and sealed from air leaks, so that the snow on the roof doesn’t melt when the temperatures outside are still freezing, the contractors say. Also, when having a new roof installed, a rubber membrane or ice shield under the shingles can be installed to prevent water from getting into the wood decking underneath.
But for now, they say, the best way to prevent the problem is by getting snow off the roof with a “roof rake” on an extended pole, Philben said.
“And don’t wait for a two-foot storm, you should do it all the time, and you have to jump on it really quickly,” Philben said. “Do it when you’re shoveling your driveway and your walkways. Because these things form really, really quickly, especially in older homes.”
It’s also possible to use ice melt to create channels on your roof that allow the water to drain, Robillard said.
“I recommend just using nylons, like leggings, filled with calcium chloride,” he said. “You put them vertically every four feet ... it will melt as the snow hits it and it will stay open for as long as there’s calcium chloride in that nylon and it’ll just allow drainage.”
Although for safety’s sake, it’s best to stay off the roof, Robillard said.
“Let the professionals do that,” he said. “If you are hiring someone to go up the roof, make sure that they provide you with a liability and a workers’ comp certificate. Make sure they’re insured.”
Icicles coming off the roof can be a sign of ice dams, he said.
“[But] if you are trying to knock off the icicles, be super careful with that,” he said. “They will come down and they could kill you. They could penetrate you, hit you in the head, cause concussions,” he said.
“It’s very, very dangerous dealing with ice dams,” Robillard warned.
Ice and snow are likely to start melting as temperatures warm in the coming weeks, meteorologist Dave Epstein said.
“As we go through the next couple of weeks with temperatures in the 30s to near 40, we’re going start to see that naturally break up,” Epstein said. “And I suspect that folks that have had ice dam issues probably should see it slowly improve. Although as it melts — when the ice dams are still present until they’re gone — you may actually have an increase in activity temporarily here, before things really start to thaw.”
