Ice dam risk in Charlottesville, VA
Will your roof get ice dams in Charlottesville, VA?
2.3 dam days a winter
Low risk. On an ordinary house in Charlottesville, conditions for an ice dam come on about 2.3 days in a normal winter, mostly in February and January.
Charlottesville averages 17 inches of snow a year and about 14 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 Charlottesville
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 2.0 | Low |
| Typical, some insulation, not air-sealed | 2.3 | Low |
| Older or poorly insulated, warm attic | 2.8 | Low |
The attic matters less in Charlottesville than in colder towns: there are only 0.3 days a winter between a typical attic and a sealed one.
What to do about ice dams in Charlottesville
- 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.
Charlottesville winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 3.9 | 4.4 | 0.9 |
| February | 5.9 | 4.9 | 0.9 |
| March | 3.8 | 1.8 | 0.2 |
| November | 0.2 | 0.0 | 0.0 |
| December | 3.2 | 2.8 | 0.4 |
Charlottesville next to nearby towns
Charlottesville ranks 18 of 39 Virginia cities here for ice-dam days, behind Winchester at 4.7 days.
- Waynesboro, VA 23 mi, 3.9 days
- Staunton, VA 32 mi, 3.9 days
- Harrisonburg, VA 35 mi, 4.2 days
- Culpeper, VA 40 mi, 4.5 days
- Fredericksburg, VA 57 mi, 1.6 days
Where these numbers come from
NOAA 1991–2020 climate normals from Charlottesville 2W, 2.0 miles from Charlottesville. 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.