Ice dam risk in Sterling, CO
Will your roof get ice dams in Sterling, CO?
11.5 dam days a winter
Moderate risk. On an ordinary house in Sterling, conditions for an ice dam come on about 11.5 days in a normal winter, mostly in January and December.
Sterling averages 37 inches of snow a year and about 43 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 Sterling
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 8.1 | Moderate |
| Typical, some insulation, not air-sealed | 11.5 | Moderate |
| Older or poorly insulated, warm attic | 15.8 | High |
Sealing and insulating a typical attic takes out about 3.4 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 15.8 days.
What to do about ice dams in Sterling
- 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.
Sterling winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 4.7 | 10.5 | 3.3 |
| February | 6.4 | 9.8 | 2.9 |
| March | 5.6 | 4.1 | 0.9 |
| April | 5.1 | 2.3 | 0.3 |
| May | 0.9 | 0.3 | 0.0 |
| September | 0.4 | 0.1 | 0.0 |
| October | 2.3 | 1.5 | 0.1 |
| November | 5.0 | 4.1 | 0.9 |
| December | 6.2 | 10.2 | 3.1 |
Sterling next to nearby towns
Sterling ranks 19 of 53 Colorado cities here for ice-dam days, behind Steamboat Springs at 51.0 days.
- Fort Morgan, CO 40 mi, 6.7 days
- Evans, CO 84 mi, 10.0 days
- Greeley, CO 84 mi, 10.0 days
- Severance, CO 88 mi, 11.6 days
- Scottsbluff, NE 90 mi, 11.1 days
Where these numbers come from
NOAA 1991–2020 climate normals from Leroy 5 WSW, 12.9 miles from Sterling. 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.