If you have multiple roos of mixed breeds, and wish to keep bloodlines pure, it's a little more difficult. Ok, a lot. I love my entire flock (currently: three roos and fifteen hens) being able to forage and learn to live peacefully during the Fall and Winter, after breeding season is done. But come an itch to hatch, I have to be sure to separate them into breeding groups. Because chickens can, as you may have heard, FLY, (as well as climb fences at times!) it isn't as easy as two pens.
To be really sure, I have planned out a breeding pen, within, the regular pen, with netting over top. This allows me to keep three groups separate--the Black Javas, to the left, in their own pen; a breeding group (A) in the pink area and coop, with barriers to prevent them going into the part of the coop where group B sleeps and lays eggs, and from the outer pen where group B will forage and run around (when not free ranging on our property). The breeding pen gives the French Coppered Black Marans roo, Jules, and his FCBM hens, Ameracauna hens, and Olive Egger hens enough room to peck and scratch, but I wouldn't feel comfortable keeping them in an enclosure that small forever (though people do!) Covered by deer mesh netting, I'll know the hens aren't flying out to get mated by the other roos, and that other roos aren't flying in to mate with them.
The coop below used to just consist of an A-frame. Wehn we got/hatched more birds, we added on the high rise coop on the left. Now we turn this coop back into two coops each Spring in Summer, by stapling in chicken wire to separate the two living quarters. This lets us accomodate sequestered breeding groups, broody mamas on eggs, and a nursery area for chicks or chicks with mamas.
This shows the breeding coop's bird door. We will cut the fence at the corner of the pen shown here, and re-attach via clips (dog leash snap-clip style, most likely) to fencing at the t-psot. That will give us a cheap and easy "gate" so we can get in the pen in case of emergency, and allow us to open and close the door easily. By the way I HIGHLY recommend this type of hinged door that opens UP. Stays out of the rain if your roof overhangs a little, and keeps shavings/poo from getting in the hinge area (problem I have with another long door on this coop, on the opposite side--see below).
This shows the left side of the breeding coop, and the boundaries of the breeding pen (t-posts). Note the area under the "high rise"--provides some protection from rain. Chickens generally don't mind rain unless it is really storming, but they don't go into their coops to get out of it. They do sometimes stay in their coops for major SNOW conditions, but not rain. They prefer to hang out under an overhang of some sort during storms. This overhang also allows me to keep their food dry. I will likely lean tin or somesuch against the coop, in that area. to provide a windbreak and a little more dry room for them to gather.
This shows the egg door for my breeding group (on end of a-frame). You can see the handles from when we built this to be a mobile coop, and the area beneath the a-frame. that is fenced in for shelter. The high rise, to the right of the egg door, is the secondary addition, and expanded our original coop's capacity from about 5 birds to about 15. The egg door is important. I plan for it to be *outside* the confines of the breeding pen, which will but up against the long handle on the right, leaving the egg door accessible. That way I can quickly gather eggs without taking much of a chance on letting sequestered birds out. The long door open to the left shows the coop space for Group B, which is made up of a Roo and hens I'll be sequestering for the next hatch (soon after Group A's sequestration is ended. I want chicks to be no more than 21 days or so apart, as you can combine birds that are no more than three weeks different in age, even without a mother hen, once the youngest group is about 6-8 weeks old.)
This just shows the netting we will use to cover the breeding pen. It is extremely cheap, at about $14 for 7'x100' at Lowe's. It is flimsy, but it doesn't take much to keep a bird from flying out of a pen. We may put up two layers if it seems too flimsy.
The pen should be finished tomorrow, and I put the barrier in the coop and sequester the birds. I can start collecting eggs and be sure they are all fathered by Jules 8 days after I separate them from the rest of the flock. I can almost hear the tiny peeps of chicks nearly ready to hatch!