Roof load - Photovoltaic system - Increase necessary?

Hello,

there is the consideration to install a photovoltaic system on the roof. Is the roof load sufficient nowadays? That is, can the given roof load still support a photovoltaic system on one side of the roof, or is it necessary to have the roof load increased? Where exactly can I find out the current roof load in the structural engineering documents? A pitched roof with a 45-degree angle would be given.

A solar installer I contacted said that there is no problem, or rather that there has never been an issue with the systems he has installed so far.
Or the other aspect is, if someone installs a photovoltaic system after several years, it will certainly be installed "simply" as well.

Any thoughts on this or even from personal experience?

Thank you very much!

Don't just think about the roof load, but also the wind load. Also inquire about fire protection and fire load registration. "Dat is noch immer joot gegange" from the solar installer (rarely a roof specialist, usually an electrician) would not be enough for me.

And also regarding the snow load

No, I don't think there should be any problems. Our roof, for example, is not even allowed to have roof tiles, but photovoltaic always works. The modules are so extremely light that it doesn't cause any problems. In our case, the structural integrity was definitely checked. That means I dug out the documents and copied them to the solar installer.

Pressure and suction are two different directions of force application. Depending on how the house is positioned and how the system is installed, one ends up with a few square meters of "sail area" on it. Combined with unfavorable attachment points, a strong storm can damage even houses built in Germany to the point of collapse hazard.

There are a number of standards and strange gaps in their application. For example, it is sufficient if the solar installer provides a description of the substructure. That is cheap and therefore he is done. For this reason, solar installers usually do it this simply, as they are electricians and not structural engineers, and everything that complicates the sale is omitted as much as possible. In case of damage, however, the insurer then wants to see an expert report in which wind and snow loads have been checked.

Of course, it is up to the OP personally how he approaches this issue. Ignoring wind load is, in my opinion, comparable in one respect to driving a car without a seatbelt. Many do it and can report that nothing happened.