Ice dam risk in Lafayette, IN
How often ice dams form in Lafayette
9.9 dam days a winter
Moderate risk. On an ordinary house in Lafayette, conditions for an ice dam come on about 9.9 days in a normal winter, mostly in January and February.
Lafayette averages 21 inches of snow a year and about 34 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 Lafayette
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 5.3 | Moderate |
| Typical, some insulation, not air-sealed | 9.9 | Moderate |
| Older or poorly insulated, warm attic | 15.7 | High |
Sealing and insulating a typical attic takes out about 4.6 days a winter here. It does not move the risk band, but it shortens every dam. An older house with a warm attic should expect closer to 15.7 days.
What to do about ice dams in Lafayette
- 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.
Lafayette winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 6.6 | 13.3 | 4.5 |
| February | 5.8 | 9.3 | 2.8 |
| March | 3.1 | 3.7 | 0.7 |
| April | 0.4 | 0.2 | 0.0 |
| November | 0.6 | 0.9 | 0.1 |
| December | 4.0 | 7.0 | 1.9 |
Lafayette next to nearby towns
Lafayette ranks 40 of 88 Indiana cities here for ice-dam days, behind Plymouth at 15.9 days.
- West Lafayette, IN 4 mi, 9.7 days
- Frankfort, IN 19 mi, 7.9 days
- Crawfordsville, IN 25 mi, 8.5 days
- Lebanon, IN 33 mi, 7.6 days
- Logansport, IN 36 mi, 10.4 days
Where these numbers come from
NOAA 1991–2020 climate normals from Lafayette 8 S, 7.4 miles from Lafayette. 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.