Ice dam risk in Washington, IN
Will your roof get ice dams in Washington, IN?
2.0 dam days a winter
Low risk. On an ordinary house in Washington, conditions for an ice dam come on about 2.0 days in a normal winter, mostly in January and February.
Washington averages 9 inches of snow a year and about 10 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 Washington
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 1.4 | Low |
| Typical, some insulation, not air-sealed | 2.0 | Low |
| Older or poorly insulated, warm attic | 2.9 | Low |
The attic matters less in Washington than in colder towns: there are only 0.6 days a winter between a typical attic and a sealed one.
Preventing ice dams on a Washington roof
- Check the gutters before the first snow and clear them, so meltwater has somewhere to go. If you see icicles thicker than a finger along the eave after a storm, that is the early sign to look at the attic.
Snowy places are not always the worst: why snowfall misleads.
Washington winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 2.9 | 3.9 | 1.0 |
| February | 2.0 | 2.8 | 0.6 |
| March | 1.0 | 0.9 | 0.1 |
| October | 0.1 | 0.0 | 0.0 |
| November | 0.1 | 0.1 | 0.0 |
| December | 3.1 | 2.0 | 0.4 |
Washington next to nearby towns
Washington ranks 87 of 88 Indiana cities here for ice-dam days, behind Plymouth at 15.9 days.
- Vincennes, IN 19 mi, 2.9 days
- Jasper, IN 22 mi, 4.1 days
- Bedford, IN 39 mi, 5.2 days
- Bloomington, IN 49 mi, 5.1 days
- Evansville, IN 51 mi, 1.6 days
Where these numbers come from
NOAA 1991–2020 climate normals from Washington 1 W, 2.2 miles from Washington. 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.