When raising birds, you can keep them in one place and bring food to them and carry the poop away, or move them often to a clean area. I would rather move animals than clean up poop. I also want the birds to forage for as much of their own food as possible. This means that I need a portable chicken coop with a mesh bottom for the poop to fall through. I wanted one big enough to comfortably house 50 birds with a nest box for between 5-7 hens per box. I also wanted it to be light enough to be moved by 1 person. The above shows the coop before the metal skin went on.
Shown above is the finished coop. Notice the 2 levels of 7 perches and the removable nest box cover over the 8 nest boxes. The top sides can be open or closed depending on the weather. The 1" mesh floor allows the poop to fall onto the grass below the coop. The 10" pneumatic tires make it so it can be moved by 1 person.
I thought it would be less stressful for the birds to let them come out of the brooder on their own so I put up electronet fencing around the brooder and the coop and opened up the brooder. After about 2 hours, I ended up getting into the brooder and moving the birds out of it that didn't want to leave. I moved them around in the yard at first before moving them into the pasture.
I highly recommend not doing it this way. The birds got used to being near the house, and it has been somewhat inconvenient ever since. Even 2 years later we still have 4 birds which refuse to go to the coop at night and sleep on the back porch. I now take the chicks out of the brooder in a cardboard box and carry them to the coop which should be FAR from the house. I then feed and water them in the coop for a few days after which they happily go into the coop on their own at night and (mostly) stay away from the house.