Ice dam risk in Columbia City, IN
How often ice dams form in Columbia City
15.4 dam days a winter
High risk. On an ordinary house in Columbia City, conditions for an ice dam come on about 15.4 days in a normal winter, mostly in January and February.
Columbia City averages 21 inches of snow a year and about 49 days with snow on the ground. Most of it comes and goes within a few days. The conditions that make a dam need all three at once: snow, cold at the eave and heat above it.
What your attic does to that number in Columbia City
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 7.7 | Moderate |
| Typical, some insulation, not air-sealed | 15.4 | High |
| Older or poorly insulated, warm attic | 24.9 | High |
Sealing and insulating a typical attic takes out about 7.7 days a winter here. It drops the risk from high to moderate. An older house with a warm attic should expect closer to 24.9 days.
Preventing ice dams on a Columbia City roof
- Air-seal the attic floor: the gaps around the hatch, light fixtures, plumbing stacks and the top plates of interior walls. This is the fix that removes the cause, and it usually costs less than a season of contractor ice removal.
- Rake the bottom three or four feet of roof after any storm that leaves more than about six inches, from the ground with a roof rake.
- At the next reroof, ask for ice-and-water membrane under the shingles from the eave to at least 24 inches inside the wall line. It does not stop a dam; it stops the leak when one forms.
Which to spend on first: air sealing or heat cable.
Columbia City winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 7.0 | 17.1 | 6.1 |
| February | 6.5 | 15.9 | 5.1 |
| March | 3.0 | 4.5 | 0.9 |
| April | 0.3 | 0.2 | 0.0 |
| November | 1.2 | 1.8 | 0.3 |
| December | 3.4 | 9.8 | 2.8 |
Columbia City next to nearby towns
Columbia City ranks 7 of 88 Indiana cities here for ice-dam days, behind Plymouth at 15.9 days.
- Huntertown, IN 17 mi, 12.0 days
- Fort Wayne, IN 18 mi, 11.4 days
- Huntington, IN 20 mi, 10.5 days
- Warsaw, IN 20 mi, 15.8 days
- Kendallville, IN 22 mi, 13.4 days
Where these numbers come from
NOAA 1991–2020 climate normals from Columbia City, 1.4 miles from Columbia City. A dam day is a day with snow on the roof and freezing at the eave while heat or sun melts the snow above it. This describes a normal winter, not this one.
- Snow-on-the-ground counts come from a second, nearby station, because the closest one does not record them.