Many on this site use the 4sq ft in the hen house and 10sq ft in the run. So 50"x85" is about 29.5 sq ft or 7.4 chickens. While the 12'x50' is 600 sq ft or about 60 chickens. You'll need to predator proof everything to make it safe for chickens. Have fun. Remember each persons set up is...
Consider having part of your run covered so the hens can come outside in bad weather. Our run is predator proof so we allow our hens 24/7 access to it and keep the food and water there, but we live in S. CA. very different winter weather then you'll be facing. Good luck and enjoy.
I feel your pain... 3 years ago our daughter brought 8 chicks home from school in a large cardboard box. Didn't realize what it was going to take or that we had a vacation scheduled. They ended up living in our family room on a sheet of plywood (on a tarp) in a simple hoop coop for about a...
I might try filling up past the wire floor with shaving to pad the feet. You might have to put something in side the cadge to keep the shaving from falling out.
This was our chicks first outside home. You could tuck it something like it in a corner. You may not be able to see that there is 1/4" hardware cloth on the windows. We also added plenty of bolts to hold it together. Yes, we all ready had the playhouse and the kids were happy to turn it over...
Sounds like it may be perfect for you.... I guess I was in-visioning it in the main part of your yard. I've found staying flexible with our girls helpful. Have fun.
Many on this site suggest 4 sq ft of house space for full size chickens. This design only provides 8sq ft so would house about 2 hens. I love this design for it's simplicity, and as someone new to chickens, plans are so helpful! Here is anther set of plans and a post on space.
Purina Hen...
I'm with OEG Lifer, if the run is predator proof you can allow the hens 24/7 access so you don't always have to be there at dusk to lock them up or you can go away for the weekend. Also, you don't have to get up to let them out, I like sleeping in. Also, no one mentioned rodents, 1/2" hardware...
Here's one I wished I'd seen, we just winged it. The Purina Hen house can be scaled to fit your needs. Move doors and windows around to meet you needs.
http://poultry.purinamills.com/NUTRITIONMANAGEMENT/HenHouseHutchDesign/default.aspx
Good luck and enjoy the adventure
Many on this site suggest 4sq ft in the hen house and 10 sq ft in the run if they never or rarely get to free range. I'm assuming the 4x4 is the run for the house you've shown. So I'd think that's way too small. Good luck, sorting out our set up was tough.
One advantage of Conny's set up with an attached run, if the entire coop is predator proofed, if you leave the door open between the house and run open, the hens can go out in the run as soon as they're up so you can sleep in or if you go away for a few days they can still be outside. Its still...
I think most set the 2x4 so they can roost on the wide, 4", side. This also allows them to keep their feet warm by sitting on them. Beautiful set up. Glad you get to keep them. Hope your neighbor doesn't find other ways to make trouble.