My husband found a coop design that he is just starting to build. It is a coop with a run underneath. The nest boxes are not raised from the coop floor, and he is placing a 4-6" board at the entrance to the nest boxes to keep the straw/hay in the boxes. The roosts will be a bit higher in the coop. Is it ok to have nest boxes that are not raised? He is afraid if he raises them, they may be nearly as high as the roost, and the chickens will want to sleep (and poop) in their nest boxes. Thanks for any advice!