[tfourb]

This is news to my solar installation, which is not fixed to my roof structure at all. My roof is not that steep, so the panels are simply put of frames which are weighed down with concrete pavers. And this is not DIY job, but professionally installed with warranty and everything.

Similarly, most solar installations on steeper roofs here in Germany are either made without penetrations at all (by hooking special frames into the roof structure under the roof tiles), or they use very basic screws that tie into the existing roof structure. Our neighbor did his solar installation himself on a pretty steep roof, something you would absolutely not do if there were any risk of structural damage.