Solar Panels and Snow Load
Solar Panels and Snow Load
(OP)
Does anyone know of any literature that addresses snow loads and solar panels? Every time I confront the manufacturer of the panels they said they don't increase the snow load on the roof. It drives me crazy that this is never really addressed. Attached is a sample photo of a system my client wants to put on his roof. I find it hard to believe this type of system will not attract more snow because it would act like a "cheese grater". Not to mention this thing looks like it would put some concentrated loads on the roof.






RE: Solar Panels and Snow Load
ASCE webinar by O'Rourke
RE: Solar Panels and Snow Load
RE: Solar Panels and Snow Load
RE: Solar Panels and Snow Load
And there's this from a supplier: Link
These are good but deal with wind and seismic only:
Seismic
Wind
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Solar Panels and Snow Load
Will it change the load distribution? Instead of an evenly distributed load, now it's being concentrated on the rails down each side.
Will it create drifts? I think this is where it gets a little tricky. I`d lean towards "yes" in any location where the array is greater than 15' wide.
RE: Solar Panels and Snow Load
Racking layout must be considered, as does ballast layout for ballasted systems. You are correct that the point loads and their effect on the loading the roof structure must be considered.
There are many, many engineers getting the snow/wind reports, accounting for point loads, etc.... so don't let the solar people tell you differently. I do find that there are solar companies that just keep calling around until they get the engineer that is willing to sign off cheaply, without reviewing any background info, nor requesting reports, likely due to unfamiliarity with the in's and out's of this type of work. I would not recommend being that engineer.