Ice dams

[Tom7227]

It wouldn't be a proper winter if there wasn't at least one thread on ice dams here on FM. Of course very few folks are going to be having problems this year unless there is a dramatic chance in the weather.

What's your favorite solution for ice dams?

[Eric Wettschreck]

Spray em down with the garden hose. At least spray a channel in them so things can flow.

[BoxMN]

In my 1940's 1.5 story (lots of these style homes have ice dam probs) I simply laid a heat cord (got one 100 footer at Ace, but "M" has them cheaper) in the valley on front and back, and down in the gutter to allow an escape route for any backed up water. So far has worked great. I just plug it in when there is decent amount of snow on the roof.

I used to use roof rake and that totally damaged my shingles in the valley area. If you use a rake, get one with wheels rather than a "scraper" it will work better.

I also re-blew my attic insulation, but need to work second story kneewall insulation and on vents a bit more.

[CAMAN]

Most permanent and least costly solution would be to add more insulation to the attic. Around R50 is what you're looking for.

[WallEYES]

Fill your wifes old nylons with rid ice to make a log and lay them on the roof about 2-3 feet up or where your interior wall line starts

[K_Josh87]

Proper ventilation of the attic space is KEY, next is air transfer. You would be much further better off, say in an older home, with poor ventilation, and poor vapor barriers to vac out/ remove existing insulation, closed cell spray foam even an inch or two thick, and follow up with blow in fiberglass/cellulose. Your biggest problems will come from the air leaks and insufficient ability to get cool air in the attic, also a major cause of pre mature roof covering failure...

[dougger222]

Spraying the ice dam with a garden hose will only cause it to leak.

Last year we ran 3 steamers and when the diesel fuel ran out of the hot box non heated water did nothing to melt the ice. You gotta get to about 250 degrees to really melt it away.

One trick I learned about getting rid of ice dams. If you can wait for a sunny day above freezing it will cost a fraction to get rid of the ice dams compared to a cloudy day below zero. Big ice dams now, really cold day 10ft an hour, warm day 30ft+ an hour.

As a general contractor specializing in roofing like others have said the root of the problem is quite often ventilation and insulation. However even on some new homes with proper ventilation and insulation with complicated roof structures ice dams can occure.

[dougger222]

If I had $5 last Winter for every caller who had a leaky roof...

This year? NONE!!!

My theory is even if we got hit with a lot of snow next week it's too warm to cause any serious ice damming. This time last year it was game over for our steamers.