Ice dam risk in Papillion, NE
How often ice dams form in Papillion
14.4 dam days a winter
Moderate risk. On an ordinary house in Papillion, conditions for an ice dam come on about 14.4 days in a normal winter, mostly in January and February.
Papillion averages 36 inches of snow a year and about 46 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 Papillion
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 7.6 | Moderate |
| Typical, some insulation, not air-sealed | 14.4 | Moderate |
| Older or poorly insulated, warm attic | 22.8 | High |
Sealing and insulating a typical attic takes out about 6.8 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 22.8 days.
Preventing ice dams on a Papillion 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.
Papillion winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 8.6 | 15.2 | 5.4 |
| February | 10.9 | 13.3 | 4.5 |
| March | 5.4 | 5.0 | 0.9 |
| April | 1.0 | 0.4 | 0.0 |
| May | 0.2 | 0.0 | 0.0 |
| October | 1.2 | 0.4 | 0.0 |
| November | 1.3 | 1.5 | 0.3 |
| December | 7.8 | 9.8 | 3.2 |
Papillion next to nearby towns
Papillion ranks 3 of 16 Nebraska cities here for ice-dam days, behind South Sioux City at 19.2 days.
- La Vista, NE 3 mi, 14.4 days
- Bellevue, NE 7 mi, 12.2 days
- Omaha, NE 8 mi, 12.2 days
- Council Bluffs, IA 13 mi, 12.2 days
- Fremont, NE 29 mi, 12.8 days
Where these numbers come from
NOAA 1991–2020 climate normals from Gretna, 8.9 miles from Papillion. 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.