Ice dam risk in Omaha, NE
Will your roof get ice dams in Omaha, NE?
12.2 dam days a winter
Moderate risk. On an ordinary house in Omaha, conditions for an ice dam come on about 12.2 days in a normal winter, mostly in January and February.
Omaha averages 27 inches of snow a year and about 40 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 Omaha
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 6.7 | Moderate |
| Typical, some insulation, not air-sealed | 12.2 | Moderate |
| Older or poorly insulated, warm attic | 19.0 | High |
Sealing and insulating a typical attic takes out about 5.5 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 19.0 days.
What to do about ice dams in Omaha
- 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.
Omaha winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 7.2 | 13.8 | 4.9 |
| February | 7.8 | 11.3 | 3.6 |
| March | 3.0 | 3.5 | 0.6 |
| April | 1.0 | 0.3 | 0.0 |
| May | 0.1 | 0.0 | 0.0 |
| October | 0.5 | 0.4 | 0.0 |
| November | 1.7 | 1.9 | 0.3 |
| December | 5.8 | 8.5 | 2.7 |
Omaha next to nearby towns
Omaha ranks 8 of 16 Nebraska cities here for ice-dam days, behind South Sioux City at 19.2 days.
- La Vista, NE 6 mi, 14.4 days
- Papillion, NE 8 mi, 14.4 days
- Bellevue, NE 10 mi, 12.2 days
- Council Bluffs, IA 11 mi, 12.2 days
- Fremont, NE 26 mi, 12.8 days
Where these numbers come from
NOAA 1991–2020 climate normals from Omaha Eppley Airfield, 8.6 miles from Omaha. 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.