A bigger issue is whether the building faces high wind conditions.
PV arrays become vast sails that can produce lift.
Instead of plunging down it may take of like Dorothy! (Wizard of Oz)
Personally, I think that PV only makes sense if done down low -- never on roof tops. Eventually the casualties will mount to such a point that today's folly will be stopped.
Between fire hazards, roof falls, and sailing effects... it's the wrong place to use. It's inspired by Sci Fi writing, by those ignorant of engineering issues.
As I've posted before, most of the money for PV power is wasted on hazardous labor -- and difficult NON-UNIFORM mounting situations. There are so many different roofs to anchor to, it's tricky to get them all correct.
In this mania, there are sure to be no end of faulty installations which will haunt America for years. In the fullness of time, PV arrays will be seen as a negative during home sales: roof leaks!
The nation would've been much better off if vast arrays were merely parked in New Mexico. There are high deserts there with no one on them -- and not much wildlife, either.
They could've been, should've been, plopped down in one vast complex -- sort of a TVA or BPA for our times.
In the long run, in the larger picture, the true market for PV power is electrolysis. By generating hydrogen gas this way all of the other issues drop away.
It is obvious, though, that ultra-cheap methane makes PV sourced hydrogen gas uneconomic.
So the market for PV energy is going to be saturated quicker than you might think.
I'm in California. The only reason for PV economics is vicious government policy -- that is taxation at the power meter. We're forced to pay $0.45/ kWHr! If your home is big enough -- and the climate is warm -- your power bills go into orbit.
This billing rate has absolutely no relation to the actual cost of power to the utilities. It's a sumptuary tax forced down from above by politicians.
It's obviously ruined the upgrade after market hereabouts. Everyone is tossing out their hot tubs -- and all the rest.
