How many chickens can fit?

[Dogchickenboy]

I have this 4 x 12 run and coop together currently I have 5 hens and 1 rooster in it and they are all red sex links. How many more large fowl / silkie bantams will fit in here? and also there are 6 nesting boxes. Pictures are included.

 

[Johnn]

The general rule is 1 hen to every metre square. I dont worry about inside space that much, inside my shed it is 2m x 1m and 11 hens sleep in it. Also its 2 hens to every one nest box