Snow Buildup along Gable and Roof
I have a problem with snow melt on my home’s roof. If there are a snowstorm and snow piles up on my roof along the gable ( see pic ), when that snow melts it gets behind the Hardi Siding. That water then finds it’s way to a window on the first floor and starts leaking into the interior of my home. It’s not a ton of water, but it’s water on the interior no less. This issue only happens when 6″ or more of snow piles up and it never happens when it rains. Just to note there is a rain screen behind my Hardi siding with with RockWool Comfortboard. I think it’s 2″ think or close to that. The siding is attached to furring strips over that Comfortboard. What is a good solution that doesn’t involve ripping out the Hardi siding? I was thinking of adding Raychem WinterGuard wiring on the roof near the gable. This should help keep that area on the roof free from snow. I just don’t even know if that would work though. Most roof heat cable is applied only a few feet up from the edge of the roof and not as high as I need it to go. Any advice would be greatly appreciated.
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Replies
The “correct” solution for this would be more flashing going up behind the siding to keep water from getting into the wall. You’d need to take the siding off to do that though.
I think your idea with the heat tape would be a good bandaid. There is no reason you can’t run the cable up the roof, the only reason you usually see the cable only on the eaves is that roof heating cables are usually used to deal with ice dams, and ice dams tend to form out at the me eaves. I would use raychem’s more expensive self regulating cables here, which I have found to be very durable, reliable, and long lived. Cheap heat tapes just don’t seem to last.
Bill
Thanks for the advice Bill. The problem with running flashing all the way up is that the snow can get 5-6' high along the gable at times. The main fail point is the window flashing on the first floor most likely, which I could address eventually. I wish there was a way to keep the water from getting behind the Hardi board completely, but that seem rather wishful thinking.
A very robust WRB with all the flashing taped/sealed to it would also work, but you'd still have the issue of having to remove the siding to install it. The heat tape would be much simpler, but would be an energy hog in the winter months while it was operating (expect at least a few hundred watts, running pretty much continuously during the winter months).
I like Michael's idea of using a snow rake. You could keep the worst of the snow clear that way, and only use a heat cable as a backup plan. I think having the heat cable in place would complicate the use of the snow rake though, so it might be difficult to try to use both together here.
Bill
In a case like this, I think the best solution is to be diligent about using a snow rake. I use one like this on my roof when snow builds up: https://www.homedepot.com/p/Snow-Joe-Roofer-Joe-21-ft-Twist-N-Lock-Telescoping-Shovel-Roof-Rake-RJ204M/206402774?.