Ice dam risk in Albert Lea, MN
Ice dams in Albert Lea, MN: how often
31.7 dam days a winter
High risk. On an ordinary house in Albert Lea, conditions for an ice dam come on about 31.7 days in a normal winter, mostly in January and February.
Albert Lea averages 40 inches of snow a year and about 84 days with snow on the ground. Snow that lies that long is what turns a little attic heat into a ridge of ice at the eave. 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 Albert Lea
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 12.2 | Moderate |
| Typical, some insulation, not air-sealed | 31.7 | High |
| Older or poorly insulated, warm attic | 56.1 | Severe |
Sealing and insulating a typical attic takes out about 19.5 days a winter here. It drops the risk from high to moderate. An older house with a warm attic should expect closer to 56.1 days.
What to do about ice dams in Albert Lea
- 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.
- At the next reroof, ask for ice-and-water membrane under the shingles from the eave to at least 24 inches inside the wall line. It does not stop a dam; it stops the leak when one forms.
Which to spend on first: air sealing or heat cable.
Albert Lea winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 8.9 | 25.6 | 11.3 |
| February | 9.8 | 20.6 | 8.3 |
| March | 6.6 | 14.1 | 3.9 |
| April | 2.8 | 1.8 | 0.2 |
| May | 0.3 | 0.1 | 0.0 |
| October | 0.3 | 0.1 | 0.0 |
| November | 2.7 | 4.4 | 1.1 |
| December | 8.1 | 17.7 | 7.0 |
Albert Lea next to nearby towns
Albert Lea ranks 79 of 103 Minnesota cities here for ice-dam days, behind Hermantown at 52.9 days.
- Austin, MN 19 mi, 33.8 days
- Owatonna, MN 31 mi, 33.5 days
- Mason City, IA 36 mi, 28.7 days
- Faribault, MN 45 mi, 33.6 days
- Mankato, MN 47 mi, 30.4 days
Where these numbers come from
NOAA 1991–2020 climate normals from Albert Lea 3SE, 4.5 miles from Albert Lea. 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.