Ice dam risk in Lima, OH
Will your roof get ice dams in Lima, OH?
6.7 dam days a winter
Moderate risk. On an ordinary house in Lima, conditions for an ice dam come on about 6.7 days in a normal winter, mostly in January and February.
Lima averages 19 inches of snow a year and about 22 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 Lima
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 3.4 | Low |
| Typical, some insulation, not air-sealed | 6.7 | Moderate |
| Older or poorly insulated, warm attic | 10.9 | Moderate |
Sealing and insulating a typical attic takes out about 3.3 days a winter here. It drops the risk from moderate to low. An older house with a warm attic should expect closer to 10.9 days.
What to do about ice dams in Lima
- 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.
Which to spend on first: air sealing or heat cable.
Lima winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 6.0 | 9.2 | 3.1 |
| February | 5.1 | 8.4 | 2.5 |
| March | 2.8 | 1.8 | 0.3 |
| April | 0.1 | 0.1 | 0.0 |
| November | 0.4 | 0.3 | 0.0 |
| December | 4.1 | 2.6 | 0.7 |
Lima next to nearby towns
Lima ranks 140 of 176 Ohio cities here for ice-dam days, behind Euclid at 24.8 days.
- Van Wert, OH 26 mi, 6.0 days
- Celina, OH 27 mi, 5.7 days
- Sidney, OH 31 mi, 7.8 days
- Bellefontaine, OH 32 mi, 11.6 days
- Findlay, OH 33 mi, 10.6 days
Where these numbers come from
NOAA 1991–2020 climate normals from Lima Wwtp, 1.4 miles from Lima. 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.