Ice dam risk in Pleasant Prairie, WI
Will your roof get ice dams in Pleasant Prairie, WI?
13.7 dam days a winter
Moderate risk. On an ordinary house in Pleasant Prairie, conditions for an ice dam come on about 13.7 days in a normal winter, mostly in January and February.
Pleasant Prairie averages 36 inches of snow a year and about 44 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 Pleasant Prairie
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 6.6 | Moderate |
| Typical, some insulation, not air-sealed | 13.7 | Moderate |
| Older or poorly insulated, warm attic | 22.7 | High |
Sealing and insulating a typical attic takes out about 7.2 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 22.7 days.
Preventing ice dams on a Pleasant Prairie 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.
Pleasant Prairie winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 11.3 | 18.1 | 6.5 |
| February | 9.8 | 12.4 | 4.0 |
| March | 5.7 | 5.4 | 1.1 |
| April | 0.8 | 0.4 | 0.0 |
| October | 0.1 | 0.0 | 0.0 |
| November | 1.5 | 1.2 | 0.2 |
| December | 7.0 | 6.6 | 1.9 |
Pleasant Prairie next to nearby towns
Pleasant Prairie ranks 98 of 98 Wisconsin cities here for ice-dam days, behind Wausau at 41.6 days.
- Kenosha, WI 4 mi, 13.7 days
- Zion, IL 5 mi, 13.7 days
- Beach Park, IL 6 mi, 13.7 days
- Antioch, IL 10 mi, 20.1 days
- Lindenhurst, IL 10 mi, 20.1 days
Where these numbers come from
NOAA 1991–2020 climate normals from Kenosha Wwtp, 4.4 miles from Pleasant Prairie. 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.