Has anyone designed a coop with a removable tray or something similar under the roost for ease of cleaning? If so, I'm curious what your design was and how you like it. I'm working on my second coop and had a couple things I wanted different, this being one.
I built a "cat litter box" under the roost. I fill it with Sweet PDZ, a naturally occurring mineral sand (can be purchased at Tractor Supply or similar farm supply stores) used in horse stalls to absorb the amonia from urine and keep the smell down of horse droppings. It works well to dry out the chickens droppings. This has several benefits. It keeps the smell down and keeps the flies way down. It last a long time because I use a cat litter scoop to sift out the droppings and leave the sand in the box. I do this every Saturday and it takes less than 10 minutes.
We have a fixed poop board filled with Sweet PDZ. It gets sifted out daily using a mesh paper tray and dumped on the compost pile. Only takes a few minutes.
I use plastic over-sized trays that sit about 6 inches under the roost bars. They work great! I scrape and hose them off daily. Takes less than 10 minutes to get it done.
The trays sit on 3 1x3 boards lined up parallel to each other under the roosts with about 7-8 inches between them. I may switch to 2x4's though because the 1x3's are fairly flimsy and I've noticed the hens actually walking and laying on the trays when they initially go in for the night. I can see the bend in the boards so since yours is a new setup, I'd go with 2x4's for the tray supports.