Instead of tarping the coop itself, use the tarp like a shade sail. You will have to run long ropes from your fencing or something like a pop up tent, like the ez ups that vendors use at fairs and farmers markets.
There has to air movement. A tarp tight and close to the ground gives no...
I have never been a fan of the deep litter method. After trying it for a year, I went back to my standard cleaning weekly.
Even when I turned it and the chickens helped, there was still ammonia build up. Sawdust cakes up then hardens and respiratory issues. All because of the deep litter...