I think just adding purlins for a typical panel install should be strong enough.I am thinking about roofing the run i am here in CT and might just use some clear panels to maybe give them some heat in the winter. I will need to strengthen roof for the snow but that will be easy enough. I will get a pic later of the inside, thanks
Looks like it's easily reachable with a roof rake or push(pull) broom if it needs to be cleared off.