Thank you for asking! There is considerable debate on this/these topics. I actually add new shavings about once a month, an inch or two. At least once weekly I toss the shavings or better, put scratch or treats in there and let the chickens toss it for me.
I also add shredded paper from time to time...and the chickens layer it for me. I clean out completely twice a year: Spring and Fall. I hose everything down including the walls and scrub with a vinegar spray (I will use soap on the floor if necessary) and a good scrub brush. The used litter from the coop goes directly into the run, where it becomes part of the compost system in my run.
The addition of PDZ (feed store) is a good idea on keeping down odor. I haven't used it but it is popular. I did sprinkle a little HYDRATED lime under the shavings as a lice/mite preventative. I also feed fermented food, which cuts down on all waste odor. Coop smells fresh and clean.
Thing is, you can read here and experiment. If you dont like shavings, try something else. It is alterable.
I could not possibly use sand in my very cold climate. It appears it can become a maintenance issue and an illness issue as well...plus it is hard underfoot for the chickens. I would rather give them something soft underfoot they can dig in and land on comfortably from the roosts.
PS No matter what, there will be dust. No matter what you use. Fact of chicken coops. The twice yearly clean out helps, plus an interim soft brushing of coop walls once in a while.
