So
@Corrie Wagoner, I have the exact same setup except I do have a wall down at the backside (which would be on the North side for me). Everybody kept telling me to use this awesome space and its 50x20(or30). So I'm going to tell you everything I've had to deal with. I'm in Texas so I'm hoping it will be different for you.
1. Originally I had the door facing East. Mistake. For me the East faces a pasture and all the coyotes and Mother Nature watched those babies go in and out and basically made a restaurant for them. They could see I wasn't on that side of the pen. So make sure your outside door faces either where you can see them anytime or the area you're around most often. I ended up moving the door to the south side which faced my yard and I could see coyotes even.
2. Excellent for winter, they were warm in the coop and the pen was relatively warm because it was protected from the North wind. Sucks big time in the summer. No air circulating back there where the wall is. We are going to put "windows" in the wall between the shed and lean-to and hardware cloth on both sides of "windows" and I'm hoping air will circulate down in that area. When there is no wind it is stifling, to the point they don't even sleep in the coop, I have huge, wide and tall ladders I made for them to roost on just so they had room to have some air around each of them.
3. Rats and mice have had a free for all digging under the tin walls. We have plans to go in and either run hardware cloth or dig a trench and pour in cement.
4. When it rains, it is incredibly wet on the farthest point from where the North wall connects to the west wall. So the SE side.....which is where the door is, we will be installing gutters.
5. My hens started getting sick and finally, after reading BYC and an article a man who keeps goats wrote, I have determined my soil has crap in it from years of use by cows and who knows what. I'm putting sand in my pen to help but I did read that using a torch on the dirt floor could help to "sterilize" it somewhat. The man with the goats says almost every time he moves kids (baby goats) into his barn or lean to they get a respiratory infection or they become ill and die. He says more of them live being birthed and staying in the pastures. I don't know whats in my dirt but my girls have had "colds", worms, mites (the mites and possibly worms but maybe not on the worms came from chickens I brought in from someone else and I was new to chickens and didn't know they should be quarantined and checked at that time. My friend who also took some of these peoples chickens said later on she found mites all over hers which sent me on my search.
6. Because there is so much space between the outside posts. we took cow gates and cow panels and wired them to the posts and then hung hardware cloth from the ceiling using zipties and ran them down the inside of the panels and gates. I used a 10x10 dog kennel and the door of it is the door to the outside. I have a door on the other side into the pen. I like this because I can fill all the water pans and food pans and put them in there, shut the door behind me and open the door into the pen and the chickens can run in and start eating or drinking (if they are having to be in there all day) or I can move the pans into the big pen area. I just didn't want them to be able to shoot directly out of the pen everytime the door was open. It gives me a buffer. I have landscape cloth over the top of it so they won't be in there when I go in.
7. What do I love about the pen? They have so much space...even with big coops in there. Nobody is crowded. They free range everyday unless its a stormy day (I found most of my chickens have been killed on stormy days....I'm not outside and there's nobody working outside). So except for the hens having to sit in nesting boxes that to me would be like cookers, its a great space that just needs a few things upgraded. I even have a sink so I can wash their dishes (its just connected with a water hose to my house outside faucet) and give them fresh water everyday.
8. During the winter I hang tarps up, with bungee cords and zip ties, along the outside walls down from the north wall to halfway to the south wall. That way the north end gets no wind, even though some of them are in the coops, some stay on those ladder roosts and stay together. They get to decide where they want to be in the winter. If I know its going to be below freezing I pick them up and shut them up in a coop.
9. Some of them have decided to roost on the dog kennel so sometimes thats a pain in the bumm but I know they're safe. We ran hardware cloth from the ceiling to the top of the kennel, then we put hardware cloth all over the door and extended it over the open part of the door so when the door is shut hardware cloth covers the space between the door and frame. Saw someone had used wood so I'm changing that.
10. Well if you made it this far without your face falling into your plate of food you are awesome!
Please don't think I'm discouraging you from using this space, maybe none of this will happen because you live in a different state. Perhaps you'll have your own unique pros and cons (shoot me a post when you have something that worked for you or didn't work for you, I'm open to suggestions always)
[Edited]....forgot to tell you I put pavers (big ones) all on the outside of the dog kennel side so when it rained from the East or South I wasn't walking in a big mud pit. We didn't bring the pen all the way to the south end. We stopped it the last 10 feet so I could have a "work area" and this is where I put the sink (its one of those old time fiberglass ones with tall legs) and a table to have their clean pans also. I also have their food in metal garbage cans and they sit on these pavers too.
