Does anyone know, is it ok for rain to hit bare insulation on your house?

We're getting our siding re-done, and they're taking forever to complete the process, so we literally have only insulation nailed to our house while the actual siding isn't on yet. We've had a lot of wind and rain, and I'm not sure if it's ok for it to get wet. I'm already noticing that some of the slabs are coming off, when they're nailed on! Doesn't seem right, but if it can't hurt it, I'd like to be reured. Any construction guys (or gals!) that might know??