A friend is in a poorly built house with some large areas of cathedral ceiling. He experienced ice dam leakage just about everywhere this past winter, cathedral and flat ceilings. Last winter here was a good one for dams. Wants to know what to do.
I said to consider stripping off all roofing, and doing a masterful job doing the whole thing in ice and watershield, then shingling over. This, because to fix all his venting, heat leak, and generally bad detailing stuff would involve a major structural redo.
Any thoughts?
Replies
Your idea may be the most practical but is not guaranteed to work. Depending on the particular roof I would recommend a standing seam roof which will simply shed all the snow or a cold roof with an 1 1/2" airspace above the existing roof, new sheathing and roofing. If you can improve the insulation while doing this, so much the better. Of course both these alternatives are more expensive and the additional thickness of the cold roof can be difficult blend in esthetically.
hard to say if this will fix it without seeing all the details.
The reroof with I&W will stop[ the ice from leaking in but ice will still desstroy shingles and this doesn't fix the source of the problem.
He probably needs Insulation Vapobar, and ventilation as a package with the roof.
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Excellence is its own reward!
I could look it up with Google, but I would rather have you tell me: what is Insulation Vapobar?
generic words - supposed to be a coma separating.
Sorry.
Excellence is its own reward!
At least you understand you're treating the symptom and not the disease. Naturally, you'd want to correct as many of the insulation/ventilation problems as possible, but sometimes you can only do so much. What's the pitch on the roof? As long as it's steep enough, membrane should do the trick only at the eaves. I often wonder if there is a downside to covering an entire roof with that air-tight barrier.
Al Mollitor, Sharon MA
Sounds like there is no ice membrane up there now. The best thing would be a complete tear off down to bare sheathing. Here in heavy snow country we apply the membrane five feet along the horizontal from the eave. A 12/12 roof would need 7 feet along the rake. It would be a waste of money to apply the membrane higher than that. The stuff is 100 bucks a roll around here. It is also a hazard to walk on for the roofers because it is so slippery. I reccommend a comp roof. Metal would be a big mistake in heavy snow areas.