I made a shade of palm tree branches and my chickens stay under there when it is too hot. I don't know what kind of trees you have in your area but I have realized that chickens prefer anything natural. even if you put a wooden pallet with some straw they will prefer it to anything frozen. I tend to wet dirt and they have a kind of dust bath in there. my dogs do the same.
I would like to have a silkie but some of my chickens are nasty so I was afraid to get it. I believed that BCM were sweet birds as a couple I have is very sweet, but 2 of their 3 babies are horrible. it might be due to the hired broody who was very wild. the 3rd chick has been hatched by a muscovie duck and he is a sweetheart. in the other pens I have some red sex link - bad character, and NNs - too big and bossy for the tiny silkie.
Along with the trees in the area I'm trying to get a grapevine growing on one of my coops. Now if I can get the deer to leave alone. Palm branches are a great idea and when landscapers prune them maybe I should grab some. How long do they last?