I have used all types of litter for coops. I have not tried sand (sand gets good reviews on this site). Of all the things I tried to date wood pellets have been the best. (I tried wood pellets as a last resort when pine shavings were not available.) They are super absorbent and swell up and eventually turn to saw dust. The droppings just seem to vanish and turn to dust when it comes in contact with wood pellets . Replace my litter and clean my coop every October after I harvest my garden. Works for me in my deep litter method. I do add to pellets from time to time. I have 63 trips around the sun so it is not my first rodeo. I have anywhere from 10 to 15 birds housed in my 4x8 coop. Through the winter months it froze harder than concrete with -40º temperatures. The poop froze before it could be absorbed by the pellets and there was like a crusty layer of poop in certain areas where they collectively took aim (no smell, messy feet or flies @ -40º). Come April things started to look after themselves. Oh I might add I do have poop boards 3½" below my roost that I clean every 2 to 3 days (excellent for catching eggs laid through the night). In my nest boxes I fold a feed bag to fit (nest boxes are 1 ft³). When a bag gets soiled; fold a new one; pop out the soiled; pop in the new. Easy peasy!. Chicken coop is salvaged 4x8 metal shed.