We are limited on space and I would like to build a 15 x 21 storage building with our chicken coop on the second story. I am planning to build a ramp on the outside of the building that would allow the chickens to climb up to the second story. Any advice on how steep the ramp can be? Or am I just crazy for thinking this would work? Any advice is welcome. PS: we are also considering getting ducks, would this change any design ideas?