Ice dam risk in Burlington, NJ
How often ice dams form in Burlington
5.4 dam days a winter
Moderate risk. On an ordinary house in Burlington, conditions for an ice dam come on about 5.4 days in a normal winter, mostly in February and January.
Burlington averages 25 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 Burlington
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 3.9 | Low |
| Typical, some insulation, not air-sealed | 5.4 | Moderate |
| Older or poorly insulated, warm attic | 7.2 | Moderate |
The attic matters less in Burlington than in colder towns: there are only 1.5 days a winter between a typical attic and a sealed one.
What to do about ice dams in Burlington
- 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.
More on when a roof rake is worth it.
Burlington winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 8.4 | 6.4 | 1.8 |
| February | 6.1 | 9.6 | 2.4 |
| March | 5.9 | 3.1 | 0.5 |
| October | 0.1 | 0.0 | 0.0 |
| November | 0.5 | 0.1 | 0.0 |
| December | 3.8 | 3.2 | 0.7 |
Burlington next to nearby towns
Burlington ranks 46 of 116 New Jersey cities here for ice-dam days, behind Hopatcong at 14.7 days.
- Trenton, NJ 11 mi, 5.2 days
- Philadelphia, PA 16 mi, 2.3 days
- Haddonfield, NJ 16 mi, 2.3 days
- Collingswood, NJ 16 mi, 2.3 days
- Camden, NJ 17 mi, 2.3 days
Where these numbers come from
NOAA 1991–2020 climate normals from Philadelphia/Mt Holly Wfo, 4.9 miles from Burlington. 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.