the shelves are simple and can be modified to fit whatever space you have to work with, they can be mounted with eyebolts and coated wire or set onto boards screwed into wall studs or attached to wall with hinges to allow them to be lifted up out of the way for cleaning purposes depending on your set up.
these are two separate shelves which meet at a corner, the cut outs you see against the walls allow for ramps coming up from lower shelves. Notice the sliding latch at the junction which provides the connection and end support for the shelf on the left.
Tools for cleaning, a cat litter scoop works for larger clumps but I cut the bottom out of the dust pan and covered it with two (offset) layers of fine hardware cloth to it to act as a larger sifter for more thorough cleaning. I dump the sifted waste into a 5 gallon bucket and then eventually it is all claimed by co-workers to put into their gardens.
This corner picture shows 2 sand shelves against back wall, lower one doubles as an optional location for egg and broody boxes, in fact a hen is setting on a nest tucked into the dark corner in this pic.
Play sand and PDZ make for a soft and comfy place for the birds to hang out, even when they aren't roosting for the evening, since this picture was taken I added a rounded trim board to the front edge of the shelf to make for a softer and wider spot for their feet to grip.
A few hens modeling the versatility of the shelves... room to roam back and forth looking for favored roosting spot, comfy edge to hang over and watch what is going on below and on this shelf I designed it to be much larger with the angled corner and in the far back corner we placed a 1 gallon waterer with a heat lamp over it to provide thawed water on even the coldest days.