That, and how to place the roosts and nesting boxes relative to each other. The vertical placement of things, from bottom to top, should be: nesting boxes - roosts - 24/7/365 ventilation. With additional summer ventilation at roost level (windows).
Vertical space also matters in roost...
Bedding would fall out of a floor entrance. No matter how you design it, they’ll find a way to kick the bedding over the edge and down the hole. They can fling stuff pretty high and wide. It would also be a total pain for you to access from the outside. Plan to be able to access all parts of the...