Javaferret,
I'm outside the city limits of Salem (a little north of Philomath) and have an 8x8 chicken house and a 20x80 run. I have pine shavings in the hen house and sand in the run (the run is covered, however). I haven't had any issues with moisture at all.
One other predator you might consider protecting against is coyote. We have lost 1 chicken to coyotes, but she got outside the yard fence. We have been free ranging for about a year and that is the only loss we've encountered.
I'm outside the city limits of Salem (a little north of Philomath) and have an 8x8 chicken house and a 20x80 run. I have pine shavings in the hen house and sand in the run (the run is covered, however). I haven't had any issues with moisture at all.
One other predator you might consider protecting against is coyote. We have lost 1 chicken to coyotes, but she got outside the yard fence. We have been free ranging for about a year and that is the only loss we've encountered.