Ice dam risk in Kentwood, MI
Will your roof get ice dams in Kentwood, MI?
21.5 dam days a winter
High risk. On an ordinary house in Kentwood, conditions for an ice dam come on about 21.5 days in a normal winter, mostly in January and February.
Kentwood averages 78 inches of snow a year and about 68 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 Kentwood
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 10.0 | Moderate |
| Typical, some insulation, not air-sealed | 21.5 | High |
| Older or poorly insulated, warm attic | 35.9 | Severe |
Sealing and insulating a typical attic takes out about 11.5 days a winter here. It drops the risk from high to moderate. An older house with a warm attic should expect closer to 35.9 days.
What to do about ice dams in Kentwood
- 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.
Kentwood winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 22.6 | 23.0 | 8.5 |
| February | 17.2 | 18.0 | 6.2 |
| March | 7.6 | 8.2 | 1.8 |
| April | 2.0 | 0.7 | 0.1 |
| October | 0.3 | 0.1 | 0.0 |
| November | 7.1 | 3.2 | 0.5 |
| December | 20.8 | 14.3 | 4.3 |
Kentwood next to nearby towns
Kentwood ranks 23 of 90 Michigan cities here for ice-dam days, behind Sault Ste. Marie at 48.8 days.
- East Grand Rapids, MI 4 mi, 22.4 days
- Wyoming, MI 6 mi, 22.4 days
- Grand Rapids, MI 6 mi, 22.4 days
- Grandville, MI 8 mi, 22.4 days
- Walker, MI 11 mi, 22.4 days
Where these numbers come from
NOAA 1991–2020 climate normals from Grand Rapids, 2.5 miles from Kentwood. 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.