I have an 8x8 feed and storage room in the middle of my big aviary. I keep all my feed in large heavy duty trash cans and have no bad feed or mice contamination issues. Makes it alot easier come feeding time
Do you all put the entire bag, bag and all, into the container? Or do you pour the actual feed in it? We have a plastic thing that we keep dog food in but it's in the house and I don't know if it's rodent proof. But I hate putting my arm way down in a bag of feed (just a weird quirk) so I'd rather just pour the feed into something.
I also use galvanized trash cans. I'm building a pretty large coop so I'm planning on building a little closet type thing and keeping mine in the coop. If I end up needing more room for the chickens I'll just move it into the feed room in my barn alongside the horses' grain... Which is also stored in galvanized cans. Only thing so far that the rats haven't been able to get into! I haven't had trouble with moisture at all. We keep ours in the bag and just plunk it down inside of the can but I don't think it would be an issue to dump it out into the can.
I wish I had thought of the freezer though... I had a huge chest freezer that broke a couple years ago and we paid to take it to the dump. Feed storage would have been a MUCH better use for it!!!