Ice dam risk in Greensburg, IN
Will your roof get ice dams in Greensburg, IN?
5.7 dam days a winter
Moderate risk. On an ordinary house in Greensburg, conditions for an ice dam come on about 5.7 days in a normal winter, mostly in January and February.
Greensburg averages 13 inches of snow a year and about 21 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 Greensburg
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 3.2 | Low |
| Typical, some insulation, not air-sealed | 5.7 | Moderate |
| Older or poorly insulated, warm attic | 8.7 | Moderate |
Sealing and insulating a typical attic takes out about 2.4 days a winter here. It drops the risk from moderate to low.
Preventing ice dams on a Greensburg 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.
Which to spend on first: air sealing or heat cable.
Greensburg winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 4.4 | 8.4 | 2.6 |
| February | 3.8 | 6.4 | 1.7 |
| March | 1.7 | 1.7 | 0.3 |
| October | 0.1 | 0.0 | 0.0 |
| November | 0.2 | 0.3 | 0.0 |
| December | 3.1 | 4.5 | 1.1 |
Greensburg next to nearby towns
Greensburg ranks 72 of 88 Indiana cities here for ice-dam days, behind Plymouth at 15.9 days.
- Shelbyville, IN 20 mi, 4.0 days
- Columbus, IN 25 mi, 4.8 days
- Connersville, IN 29 mi, 7.4 days
- Franklin, IN 31 mi, 6.0 days
- Greenfield, IN 34 mi, 7.7 days
Where these numbers come from
NOAA 1991–2020 climate normals from Greensburg, 0.7 miles from Greensburg. 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.