As the temps dip and the snow flies here in Southern Vermont, some of us welcome those double dealing icicles to our home’s eaves. “That’s kind of harsh language,” you’re thinking. “Icicles are pretty! They glisten in the sun adorning our homes with natural bling!” you say.
Don’t be fooled! They have a sinister side.
Icicles are a tell-tale sign of a serious problem: ice damming on a roof. Ice dams form when the temperature of the roof is not uniform. Heat from your home’s attic warms the roof slopes but not the eaves, so when the snow melts on the slope and the water meets the cold eaves, it freezes creating the dreaded ice dam. As snow continues to melt, water runs down the slope and pools at the dam that has formed at the eave.
Image taken from the National Weather Service website
What happens next is not pretty. This pooled water at the eaves can seep through the crevices between the roof’s shingles into the attic insulation, down the walls and through the ceiling. Chaos ensues! Wet building assemblies become a breeding ground for mold and mildew and you could be looking at water damage to walls and ceilings, not to mention serious damage to your roof, which is no fun.
There are some terrific articles online about how the three types of heat transfer, conduction, convection and radiation, function in a home and how they contribute to ice dams. (like this one from the University of Minnesota) But we’re going to skip to the chase in today’s blog and talk about some solutions.
Keeping the temperature of the entire roof uniform is the simplest way to minimize ice dams. You want the slopes to be as close in temperature to the eaves as possible. In order to do that you need to look to your attic.
Air sealing the attic floor will help keep warm air out of the attic, this includes caulking around light fixtures; floor seams - Really, anywhere there could be warm air escaping from the living space into the attic, you’re going to want to caulk
Flashing around chimneys
Tenting recessed canned lights and insulating well around them
Sealing and insulating ducts and making certain that all ducts exhaust to the outside - this includes bathroom fans, dryer vents, etc.
Ventilating the eaves and ridgeline; you may want to consult a professional on this one
Making sure the attic hatch that leads to the living space is well insulated and sealed
Adding more insulation to the attic space
With some simple weatherization solutions, you could say “good-bye” to ice dams and “hello” to peace of mind knowing you’re preventing a whole host of headaches. In addition, you’re home will be more comfortable and you’ll see savings on your energy bills. If you miss the icicle bling factor, you could always hang some lights!
Got an ominous ice dam you’d like us to take a look at? Give us a call at 802-387-5005 or visit us on the web at www.farnuminsulators.com.