there is a similar coop design in my signature for DIYers. the "looking for plans similar to" link. read it all the way though and get all materials lists, i kind of explained it on the fly.
if they have a large enough area to run, you can normally let the hens hatch right in with the rooster. if the area is to small the rooster will typically become "bored" and start pecking at the chicks. mom will usually protect them, it may help to put a place in the coop or run where the...
its not to complicated, after the brooder you would use a grow out pen. when they get about 20 weeks you can normally mix them without much problem. they will pick a little at first to establish pecking order, but they normally stop in a few hours.
a simple grow out pen can be made from...
ok with dual purpose, your cockerels will get old enough to fertilize the hens if not kept separate. but, 9 out of 10 people cant tell the difference between fertilized and non fertilized eggs. there is no difference in health benefits and no difference in taste.
just so you know, hatching...
if he did take care of the hens, you probably wont notice a difference in the eggs - unless you let them sit for to long.
if your using the cornish rock cross, you will butcher the cockerels before they are old enough to breed. the drawbacks of the one coop method is - its hard to mix chicks...
it is best to have 2 coops, but not necessary. by having 2 coops you can raise the protein on the meat birds yielding better meat quality and faster growth. however, you can let them run with your laying hens - they will still gain weight just fine.