I had never heard the phrase "ice dams" until the winter of 2002-2003.
That was the winter we got the big Christmas snowstorm, followed by another 20-plus-incher a couple of weeks later.
We had owned our home for about five years at that point, and hadn't had any real bad winters. Our daughter was born eight weeks premature in mid-January, so I didn't have time to pay much attention to what was going on with all of that snow on my roof.
When I came home one day in late February and saw icicles protruding through the vented soffit on the eaves of my roof, I was a little perplexed. How was water getting in there? I called a buddy who was a contractor, who told me I had big problems.
Snow had melted, then refrozen on the edge of the roof to the point that the ice that had formed was blocking water from running off. It was instead backing up and getting under the shingles.
So I shoveled the snow off, which in its own right was a beast of a project, and set to work hacking away at the ice with a hatchet. I knew to be careful, and to not bash the shingles. This went on for days, sometimes in the dark, as I knew I had to get rid of that ice before we got rain or a major thaw.
We lucked out, as I caught the problem before we had a big thaw. I have friends who figured out they had ice dams when water came pouring into their home as the snow melted.
With the snow we have had the past few weeks, it looks like we are headed to another winter where homeowners should be worrying about ice dams. I can see the signs on many houses already, a few inches of ice beginning to form on the edge, big icicles hanging off.
There are a number of reasons why some houses get ice dams and others don't. The big culprits are lack of attic insulation and ventilation, which cause the roof to warm, and the melting snow re-freezes at the eaves.
We addressed our problem with a new roof that added a ridge vent, though I am still so wary of the issue that I get as much snow off the roof as I can when we get more than 18 inches or so.
That is the best way to deal with it this winter, getting that snow off. I have learned how to shovel my roof, a few falls from our single-story addition having taught me how to position my feet and how to get on and off and shoveling down with a plastic blade shovel.
(The key when sliding off the roof is don't panic, and pick your feet up as you get to the gutters. The snow will cushion your fall if you can land right, at least from the single story height that I have tumbled. One time my feet got caught on the gutters and I landed sideways on a deck railing. That did not feel good.)
Needless to say, it's not something I recommend doing unless you are sure you can do it safely. This time of year, there are plenty of contractors who will do it. And it's a lot less hassle to pay a couple of hundred bucks now than deal with interior damage, insurance claims, etc.
-- Don Lehman