We have a mansard roof that has been giving us trouble in the winter. We have gutter guards which we love however, they add to the problem with dripping water onto our front steps which freezes making for a dangerous situation. We have gable vents with fan in the roof. We have also added additional insulation to the attic and sealed all openings and drafts, ie: attic stairs etc. The ice damming still occurs and due to the way the sun hits the roof and not the front of the house we end up with many icicles and freezing in the front.
We have had roofers suggest a ice and rain sheeting under the shingles which will prevent ice damming damage, however, we do not feel this will fix the problem. Others have suggested a ridge and sofit vent, however, these contractors feel this may not work due to the type of roof. Any suggestions are greatly appreciated. Pictures attached for your reveiw. Thanks,
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In that PARTICULAR case.. I'm tempted to advise the heated coil for under the first rows of shingle. It works much the same as heat tape on a water pipe... only it goes under the shingles and is engineered for outside use.
I have seen these things used in situations where it was TOTALLY an improper use... but if you are only getting ice dams up as far as it is in your picture... it just might do the trick.
Note.. I have not tried this... it's just a suggestion. Maybe someone else has actually done it, and can advise.
I would be reluctant to string heat tape with a cedar roof for fear of something screwing up and the house burning down. In addition, all the heat tapes do is keep channels open for water to flow from behind the ice dams, so you dont have standing water running through your roof into the walls and ceilings below. If anything, they create larger icicles than what you have now.
I didn't see much of an ice dam in your picture - mainly just snow. A couple runs of bituthane (snow and ice) under the shingles will prevent water running into your house, but will not stop ice dams from forming.
The only thing that will do that in most instances is metal roofing up the eaves 4 feet or so.
Many people are under the impression that ice dams will not form if the roof is well insulated. That is not the case in extreme climates. The alignment of the roof relative to the sun is at least as important as the insulation.
If you are not experiencing interior damage, and I suspect you are not, then I would suggest just knocking off the icicles. I use a fiberglass surveyor's rod for this purpose myself.
jim