dimensions of the hole in the coop?

[blackeast3]

I"m building a two floor coop and need a hole on the bottom of the second floor for the Orpingtons to travel through. What dimensions should the hole be for an adult chicken?

 

[Judy]

Depends on the angle of the ramp. I'd make it 10" or 12" wide, and long enough to be sure their backs don't scrape -- long being the dimension that matches the ramp in direction.