Solar Array and Ice Damming
Doing some light energy retrofit of a 100 year old house that was renovated before us taking it over. I believe the roof is actually broken into a 2 small triangles of cold roof with a central hot roof due to loss of venting channel in middle part (cathedral roof portion of finished attic). This I think has led to some significant ice damming problems more so on the southwest side. (house front door faces south).
Planning on changing out asphalt roof for aluminum standing seam (Interlock) followed by full roof solar array. Snow guards only on solar array.
Was wondering, doesn’t a solar array always solve ice damming? And therefore I can forego the expensive tear out of the Cathedral roof or external insulation? (the roof I believe has decent amount of insulation at the moment just in the wrong way…)
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Bump?
Would an extensive solar array on a roof with a history of ice damming solve the ice damming?
“Would an extensive solar array on a roof with a history of ice damming solve the ice damming?”
My gut says almost never will an array fix ice dams.
Ice dams are almost always a symptom of warm air escaping the building, if you are unwilling to fix the air leaks and insulate properly electric deicers seem to be the popular fix.
Have you found and read Martin’s articles on how to deal with your sloped ceilings?
Walta
But how can you get ice damming if snow doesn't land on the roof to melt?
Wouldn't the solar array act as a vented overroof? minimizing melt as well?
If you get ice dams regularly it's usually a sign of fundamentals gone wrong, especially air sealing and insulation (often localized insulation problems, btw). You should fix those prior to new roof and possible solar array.
Perhaps if the lowest row of panels ran all the way to the very bottom of the roof it might have a positive effect - but on most installations I've seen the panels are set back a small amount so they are out of the way of careless ladder placement. The panels will still be elevated several inches above the roof regardless of where they end, so any wind-blown snow will find its way into the space under the front edge of the panels.