How big should I make the run?

[maliciousglow]

I have eighteen chicks (RIR, Domineckers, and Black Spanish Bantams) housed in a 14 x 12ft converted shed. I'm making plans for a run and I wonder, my fellow chicken enthusiasts, would a 10ft x 10ft run be sufficient space for that many chickens? I already have a 14ft long chicken tunnel they play in that I will attach to the finished run.

 

[Ozarkhomesteader]

A good general rule for run space would be 10 square feet per Large fowl (standard) and 7.5 for bantams. More is always better though. 10x10 could do about 10 birds comfortably.

so the tunnel is not the coop? in that case that could be considered part of the run.