Ice dam risk in Sharon, PA
Ice dams in Sharon, PA: how often
16.6 dam days a winter
High risk. On an ordinary house in Sharon, conditions for an ice dam come on about 16.6 days in a normal winter, mostly in January and February.
Sharon averages 68 inches of snow a year and about 58 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 Sharon
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 8.6 | Moderate |
| Typical, some insulation, not air-sealed | 16.6 | High |
| Older or poorly insulated, warm attic | 26.5 | High |
Sealing and insulating a typical attic takes out about 8.0 days a winter here. It drops the risk from high to moderate. An older house with a warm attic should expect closer to 26.5 days.
Preventing ice dams on a Sharon 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.
- 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.
Sharon winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 19.6 | 19.0 | 6.3 |
| February | 15.1 | 15.5 | 4.8 |
| March | 10.5 | 8.1 | 1.7 |
| April | 2.6 | 0.9 | 0.1 |
| October | 0.7 | 0.1 | 0.0 |
| November | 4.5 | 2.4 | 0.3 |
| December | 14.8 | 12.0 | 3.3 |
Sharon next to nearby towns
Sharon ranks 11 of 68 Pennsylvania cities here for ice-dam days, behind St. Marys at 26.9 days.
- Hermitage, PA 3 mi, 16.6 days
- Youngstown, OH 12 mi, 16.6 days
- Niles, OH 14 mi, 9.1 days
- Warren, OH 16 mi, 9.1 days
- New Castle, PA 18 mi, 11.5 days
Where these numbers come from
NOAA 1991–2020 climate normals from Youngstown-Warren Regional Airport, 9.1 miles from Sharon. 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.