If the icicles hanging off your roof are an inch or longer, you probably have an ice dam on your hands.
When snow accumulates on a rooftop, an unevenly heated attic can melt pockets of snow high on the roof. That moisture then trickles down the roof into the gutter, where it refreezes, creating a dense clog of ice.
Given all the snow the Omaha area has seen recently, houses here are seeing footlong icicles and thick ice dams. By understanding what causes this phenomenon, homeowners can take steps to prevent them from forming.
Most of the time, ice dams are nothing to fret over. But when a large chunk of ice falls on something or someone, or an imperfect roof lets water in, an ice dam can be costly.
“If they’re an inch (in diameter) or bigger or they’re all over the place and could fall and hurt somebody, they’re too big,” said Jake Hansen, vice president of White Castle Roofing in Omaha.
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The most common way ice dams form is by poor heat distribution in an attic. They also can form when gutters or downspouts are clogged with debris, not allowing the gutters to drain properly.
When a roof has an ice dam, water can find its way into imperfections in a roof. In roofs that don’t have a weather shield or have cracks or open nail holes, water can seep in and freeze, expand and cause damage. Eventually, that water can leak into your house and cause further mayhem.
Ice dams aren’t all bad news. They can be a useful diagnostic tool.
Mark Loscutoff, president of Omaha Home Energy Analysis and Testing, said the melting and freezing patterns on your roof are clues that tell you where you’re losing heat.
“If you have a nice, even covering of snow but there are some depressed spots as the snow melts, those depressions are specific points of heat loss that are melting the snow,” he said. “If it’s more of an even melting going on, it may be a shortage of insulation in the attic or it could be a lack of attic ventilation.”
Companies like Loscutoff’s generally charge about $200 for a diagnosis of a home’s heat loss. From there, costs vary depending on the severity of the problem and what needs fixing.
During extended periods of snowfall, like this month, new companies can arrive in town, offering to remove people’s ice dams. Loscutoff warned against chipping away ice, since that risks damaging your roof, gutters and fascia. Instead, he advised buying a snow rake to remove excess snow before it melts and freezes.
According to Hansen, Omaha’s city code calls for roofers to install two layers of ice and weather shield, so roofs built to code shouldn’t be prone to damage from an ice dam.
To prevent ice dams, Elkhorn’s Absolute Roofing recommends keeping gutters clear, checking for proper attic insulation, checking exterior ventilation and confirming that your roof has an ice and water shield.
Hansen said it’s not worth risking a fall to try and break up an ice dam once it has formed. Instead, he recommends buying a heat cable, which is a long cable that feeds through a pipe, drain or gutter. If you can feed it through your gutter safely, go for it, otherwise try wrapping it around the gutter or waiting until the next thaw to install it.
“It keeps the entire gutter, and more importantly your downspout, from freezing up,” he said.
But even then, snow falls. It melts. And it gets cold again and freezes. That’s nature.
“Because of our climate, it’s going to naturally occur,” Hansen said. “If your downspout is clear and your attic is properly ventilated, that’s all you can really do.”
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Dymond Meeks leaps across the snow pile in the center of Farnam Street near its intersection with 14th Street on Wednesday as she makes her way to work. Meeks said the snow was terrible. She said it took her 15 minutes to get down the hill her home is located on.
A pedestrian (who refused to be identified) cruises past a sign of seasons to come in the window of Palm Beach Tan, 5417 S. 96th St., on Wednesday.
Motorists and pedestrians navigate around the snow piles on Farnam Street on Wednesday. Another storm likely bringing rain and snow is headed to Omaha.
Snow is lofted into the air as cleanup begins after a winter storm in Omaha on Wednesday.
Traffic moves east along West Center Road as seen from the 139th Street pedestrian bridge on Wednesday.
A man clears the snow from the top of a parking garage located near 10th and Jackson Streets on Wednesday.
Traffic moves along Pacific Street looking east from its intersection with 156th Street on Wednesday.
Christopher Watson bikes east on Leavenworth Street toward Saddle Creek on Wednesday as he heads to the University of Nebraska Medical Center.
A city plow heads north on 42nd Street north of Leavenworth Street on Wednesday.
Christopher Watson bikes east on Leavenworth Street towards Saddle Creek on Wednesday as he heads to the University of Nebraska Medical Center.
Vehicles navigate through snow after a winter storm moved through Omaha on Wednesday.
Commuters dealt with another morning of snow after a winter storm moved through Omaha on Wednesday.
Amir Begovic walk his dog Garo in a fresh coating of snow after a winter storm moved through Omaha on Wednesday.
Jen Freeman, who is training for a 100-mile race, jogs through the snow on Wednesday in the Millard area. Freeman said she has to train no matter the weather.
Henry Rahlfs Jr. on Wednesday morning uses a sweeper to remove snow from sidewalks in a shopping center located near 132nd Street and West Dodge Road. Rahlfs said he started clearing snow about 8 p.m. Tuesday and he had been working since then.
Omaha awoke to additional snow after a winter storm moved through Tuesday night into Wednesday.
An Omaha Metro bus navigates through snow after a winter storm moved through Omaha on Wednesday.
Wednesday morning traffic moves east on Cuming Street as snow falls.
Dusten Schaffer walks west on the Bob Kerrey Pedestrian Bridge from Council Bluffs to Omaha as fog rises out of the Missouri River on Tuesday.
Tom Kinsella shovels his sidewalk near 45th Street and Woolworth Avenue on Wednesday.
A toy zebra watches over icicles Wednesday as they hang on this house on 60th Street north of Sorensen Parkway.
Kaleb Starkey, 3, asks his dad Jonathan to carry him back up the hill so he can sled.
Broken sleds fill the garbage can at Memorial Park on Wednesday.
Kiya Starkey, 5, walks up the hill outside of Nathan Hale Middle School while sledding with her family on Wednesday.
Katja Starkey sleds on the hill outside of Nathan Hale Middle School on Wednesday.
Katja Starkey coaxes her 3-year-old son Kaleb onto a sled Wednesday on the hill outside of Nathan Hale Middle School.
Kiya Starkey, 5, sleds down with her father Jonathan at the hill outside of Nathan Hale Middle School on Wednesday.
Omaha Public Works crews plowed snow into the center of Dodge Street, looking east from 49th on Wednesday.
Snow is moved into a pile near Cuming Street on Wednesday.
A plow truck works in north downtown Omaha on Wednesday.
Snow falls Tuesday as pedestrians and vehicles get around downtown Omaha. The view is looking north on 17th Street to Dodge Street.
Commuters work to clear their vehicles of snow as a winter storm moves into Omaha on Tuesday.
Commuters begin a slow climb up the westbound Interstate 480 on-ramp on Tuesday.
A car drives down the ramp of the Central City parking garage at 17th and Dodge Streets on Tuesday.
Snow falls at TD Ameritrade Park on Tuesday.
A man walks west through the snow on Howard Street toward 15th Street on Tuesday.
In this Tuesday photo, the City of Omaha has piled snow in a field southeast of 72nd and Center Streets. The area awaited more snow as a winter storm moved in Tuesday evening.
The latest round of snow began falling late Tuesday afternoon and was expected to taper off by noon Wednesday.
Traffic moves along 132nd Street, just south of West Dodge Road, during the Tuesday evening commute.
Traffic moves along Blondo Street during the Tuesday evening commute. The photo is looking to the east at the intersection with 144th Street.
Commuters begin a slow climb up the westbound Interstate 480 on-ramp as a winter storm moves into Omaha on Tuesday.
Traffic moves along in north downtown near TD Ameritrade Park on Tuesday.
Cars travel along Cuming Street late Tuesday.
Snow is plowed in the parking lot of Roots Music Shop after a winter storm in Lincoln on Wednesday.
Snow covers the streets on the University of Nebraska-Lincoln campus after a winter storm on Wednesday.
Snow melts on a tree after a winter storm in Lincoln on Wednesday.
Jonathan Starkey carries his son Kaleb, 3, while daughter Kiya, 5, center, and other son Gadisa, 8, follow up the hill.
Kaleb Starkey, 3, sleds on an inflatable sled at Nathan Hale Middle School, 6143 Whitmore St., on Wednesday.
Katja Starkey rides down on a throwback snowboard.
Kaleb Starkey, 3, lies down as he sleds on a throwback snowboard.
Sledders make their way down — and back up — the hill at Memorial Park on Wednesday.