I built this outdoor play area for my kids this past summer. The area under that portion of the deck was always messy and muddy and so I wanted to make use of it. I built the deck and anchored it with lag bolts to the deck supports. On the one side I used rubber mulch and on the other there is play sand. I dug holes in various locations and filled with gravel to allow for drainage under the sand and mulch. For the awning I used plain cedar shingles. I added a shower that is just regular 1/2" metal pipe with a hose adaptor. The shower wall and fence are just old pallets that I had for a while, cut to size, which was pretty much random but they came out great. I added a misting system under the awning that works great, the kids love the cool mist on the hot days. Overall, a heavy job ripping up the grass, moving the wood, gravel, stones, sand and mulch, but a fun deck build and even better experience doing this with my kids by my side!