There is no such thing as material that is "bulletproof", only varying levels of bullet resistance can be certified to specific and highly complex applications

There is no such thing as material that is "bulletproof", only varying levels of bullet resistance can be certified to specific and highly complex applications of materials or combinations of materials. You know how car safety is complex and isn't solely attributable to any one system or component, like a seatbelt, or airbags, but rather the combined effects of the whole system of components, in that specific application? Bullet resistance is similar. My idea for this is basically an enormous, rail-guided heavy, metal garage door that can be raised remotely to cover the entire installation from above. You could even power it with a small power reserve battery that got recharged from the panels, have it automatically get raised when the barometric pressure went too low or after a weather alert for hail came in, etc. Trying to engineer resistance into the panels for the top 0.1% most extreme hail load is going to increase the cost for everyone, including those who never even get pea-sized hail. Seems wasteful to me.