For several weeks we had a lot of bitter cold weather with cold records being broken, that was during January which is typically the coldest month of the year here in Vermont. Typically temperatures run from single digits such as 8 degrees up into the 20’s. This January it was colder and there was a significant amount of snow.
As all that snow sits on your roof it is easy to see which homes are well insulated and which ones are not.
Take a look at today’s photograph. Yup, those are icicles that have been glamorized as a beautiful thing in the winter. The sun shines on them and often creates a rainbow of color. Kids love to lick on icicles as though they are a winter treat. Icicles are an iconic occurrence that everyone seems to wants in winter.
Well…………., hold on! Icicles may look pretty and all that but only if they are on someone else’s house. If you have icicles then you have a problem that should be taken care of.
What causes icicles to form:
- The snow on the roof melts from the heat in the attic.
- The very bottom layer of snow on the roof melts and runs down the roof where it freezes again in the air that is below freezing.
All of us have heard of Ice Dams but, what exactly is an ice dam?
- Ice dams form when attic heat melts the bottom layer of snow on the roof.
- The water from the melting snow runs down the roof and freezes again when it runs across the roof’s overhang.
- Under the overhang is cold air and sub-freezing temperatures that quickly freeze the water run-off.
- That brand-new ice on the overhang builds up and behind it, up on the roof under the snow, and blocks water creating a puddle
- The ice has now frozen into an Ice Dam.
Some of the water runs up and over the ice dam forming icicles but most of it will backup under the shingles and appear inside your house, whereupon everyone thinks the roof is leaking, but in reality it is the water behind an ice dam running upward under the shingles. Technically the roof is not leaking.
We will discuss Ice Dams and Icicles for a couple days.
Does your home have icicles?