Why ice dams form
An ice dam is a ridge of ice along the bottom edge of a roof. It holds back the snow that's melting above it, and that water has to go somewhere.
Put simply, the roof is warmer higher up, over the attic, and colder at the overhang. Snow melts on the warm part, runs down, and freezes on the cold part.
The National Weather Service adds that after several days of melting and freezing, water can work up under the shingles into the attic. From there it can damage ceilings, walls and what's in the house.
Ice dam weather around here
A normal January here thaws and freezes again and again. At the Bonners Ferry weather station, the January low drops to 32 degrees or below on about 28 days. The high stays at or below freezing on only about 13. That leaves about half the month thawing in the afternoon and freezing again after dark.
Source: Western Regional Climate Center, Bonners Ferry temperature summary. January freezing days checked in the station's general climate summary, 1907 to 2012, Oct 28, 2026.
The snow sticks around, too. The station's records average about 8 inches of snow on the ground in January and about 6 inches in February.
Source: Western Regional Climate Center, Bonners Ferry monthly climate summary. Average snow depth checked on the station's monthly summary, 1907 to 2016, Oct 28, 2026.
Ice dam prevention starts in the attic
The federal sources point to keeping the house's heat out of the attic, so less of it reaches the roof. The Department of Energy names three parts: good air sealing, enough attic insulation, and attic ventilation.
Air sealing closes the gaps where warm air rises from the rooms below into the attic. Insulation slows the heat that gets through. How much insulation ENERGY STAR suggests for Boundary County's climate is on the insulation page.
Who fixes ice dams
It's two jobs. The longer-term work happens in the attic: air sealing and insulation, the work insulation businesses do. Damage to the roof, and taking ice off it, is work for roofing companies.
Gutters hang right at the roof edge, where ice dams build. If yours are due for replacing, the gutters page has the questions to ask about hanging them for heavy snow.
Pricing a new roof? The roof pitch calculator works out your roof's pitch and surface area, and the metal panel count.
Costs at a glance
Nationally, ice dam removal by a pro usually costs $150 to $700 an hour, and fiberglass insulation $0.30 to $2 per square foot.
| Job | Typical cost | Sources |
|---|---|---|
| Ice dam removal by a pro | $150 to $700 per hour | Sources: [1][2] |
| Fiberglass insulation | $0.30 to $2 per square foot | Sources: [3][4] |
- Consumer Reports, How to Prevent Ice Dams From Damaging Your Home, updated October 11, 2025.
- Bob Vila, How to Remove Ice Dams And Prevent Them From Forming, updated February 2, 2026.
- Consumer Reports, How to Shop for Home Insulation in 2025, updated October 14, 2025.
- Today's Homeowner, Rockwool vs Fiberglass: Which Insulation Is Better?, updated March 13, 2025.
National ranges from the sources listed, checked October 2026. These aren't prices from businesses listed on Huck's Guide. Costs in Boundary County can be higher or lower.
Ask before you hire
These help you find the cause, not just clear the ice.
Sources
| Source | What was checked | Last checked |
|---|---|---|
| U.S. Department of Energy, Building Science Education, Eaves Sealed in Cold Climates | How ice dams form and the three fixes checked on DOE's page | Oct 28, 2026 |
| National Weather Service, Preventing Roof Ice Dams | Melting and freezing cycles, gutters and roof snow topics checked on the Weather Service's page | Oct 28, 2026 |
| ENERGY STAR, Attic Air Sealing Project | Ice dam wording checked on ENERGY STAR's attic air sealing page | Oct 28, 2026 |
| Western Regional Climate Center, Bonners Ferry temperature summary | January freezing days checked in the station's general climate summary, 1907 to 2012 | Oct 28, 2026 |
| Western Regional Climate Center, Bonners Ferry monthly climate summary | Average snow depth checked on the station's monthly summary, 1907 to 2016 | Oct 28, 2026 |