Nest Boxes Higher than ROOSTS???? HELP

[sutphindanesnchickens]

Need to know if the nesting boxes need to be lower or higher than the roosts? should the nest boxes be at floor lever or higher?
Also how deep should the litter be for the deep layer method?
Thanks

 

[sugarbush]

Ideal nest box height is 18-24 inches off of the floor, roosts placed higher than that help keep chickens from roosting in nest boxes.