IceDamCheck

Ice dam risk in Noblesville, IN

Ice dams in Noblesville, IN: how often

8.1 dam days a winter

Moderate risk. On an ordinary house in Noblesville, conditions for an ice dam come on about 8.1 days in a normal winter, mostly in January and February.

Noblesville averages 27 inches of snow a year and about 30 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 Noblesville

AtticDam daysRisk
Air-sealed and well insulated4.6Low
Typical, some insulation, not air-sealed8.1Moderate
Older or poorly insulated, warm attic12.6Moderate

Sealing and insulating a typical attic takes out about 3.5 days a winter here. It drops the risk from moderate to low. An older house with a warm attic should expect closer to 12.6 days.

What to do about ice dams in Noblesville

  1. 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.
  2. 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.

Noblesville winter, month by month

MonthSnow (in)Days on groundDam days
January8.411.43.6
February7.29.22.5
March3.62.40.4
April0.20.10.0
November0.60.40.1
December6.76.61.6

Noblesville next to nearby towns

Noblesville ranks 49 of 88 Indiana cities here for ice-dam days, behind Plymouth at 15.9 days.

Where these numbers come from

NOAA 1991–2020 climate normals from Castleton 2 S, 11.1 miles from Noblesville. 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.