Ice dam risk in Muscatine, IA
Will your roof get ice dams in Muscatine, IA?
12.0 dam days a winter
Moderate risk. On an ordinary house in Muscatine, conditions for an ice dam come on about 12.0 days in a normal winter, mostly in January and February.
Muscatine averages 24 inches of snow a year and about 39 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 Muscatine
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 6.1 | Moderate |
| Typical, some insulation, not air-sealed | 12.0 | Moderate |
| Older or poorly insulated, warm attic | 19.4 | High |
Sealing and insulating a typical attic takes out about 5.9 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 19.4 days.
What to do about ice dams in Muscatine
- 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.
Muscatine winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 7.0 | 16.2 | 5.8 |
| February | 5.8 | 10.5 | 3.2 |
| March | 2.8 | 2.9 | 0.5 |
| April | 0.7 | 0.2 | 0.0 |
| October | 0.2 | 0.1 | 0.0 |
| November | 0.8 | 1.2 | 0.2 |
| December | 6.2 | 7.6 | 2.3 |
Muscatine next to nearby towns
Muscatine ranks 38 of 41 Iowa cities here for ice-dam days, behind Mason City at 28.7 days.
- Rock Island, IL 25 mi, 14.0 days
- Davenport, IA 26 mi, 14.0 days
- Iowa City, IA 29 mi, 14.9 days
- Moline, IL 30 mi, 15.9 days
- Bettendorf, IA 32 mi, 15.9 days
Where these numbers come from
NOAA 1991–2020 climate normals from Muscatine, 0.8 miles from Muscatine. 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.