Ice dam risk in New Castle, IN
Ice dams in New Castle, IN: how often
9.2 dam days a winter
Moderate risk. On an ordinary house in New Castle, conditions for an ice dam come on about 9.2 days in a normal winter, mostly in January and February.
New Castle averages 25 inches of snow a year and about 30 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 New Castle
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 4.7 | Low |
| Typical, some insulation, not air-sealed | 9.2 | Moderate |
| Older or poorly insulated, warm attic | 14.8 | Moderate |
Sealing and insulating a typical attic takes out about 4.5 days a winter here. It drops the risk from moderate to low. An older house with a warm attic should expect closer to 14.8 days.
Preventing ice dams on a New Castle 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.
Which to spend on first: air sealing or heat cable.
New Castle winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 7.9 | 11.7 | 4.0 |
| February | 6.4 | 8.9 | 2.7 |
| March | 3.4 | 2.6 | 0.5 |
| April | 0.3 | 0.1 | 0.0 |
| November | 0.9 | 0.5 | 0.1 |
| December | 5.9 | 6.3 | 1.8 |
New Castle next to nearby towns
New Castle ranks 44 of 88 Indiana cities here for ice-dam days, behind Plymouth at 15.9 days.
- Muncie, IN 19 mi, 9.8 days
- Yorktown, IN 20 mi, 6.9 days
- Anderson, IN 21 mi, 6.9 days
- Connersville, IN 22 mi, 7.4 days
- Greenfield, IN 23 mi, 7.7 days
Where these numbers come from
NOAA 1991–2020 climate normals from NEW Castle 3 SW, 2.2 miles from New Castle. 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.