This is an excellent chain of posts - I've learned a lot.
My daughter and I started with 8 day olds back in June... just getting ready to lay now.
From the beginning we planned on the deep litter method, so I built our coop accordingly.
For our 20 birds - we have an 8x8 wood framed, insulated coop. The floor and bottom two feet of the walls are finished with pressure-treated plywood. I couldn't be bothered with linoleum etc.
Then we layered in spruce-fine-fir saw shavings (not sawdust) from a pallet plant down the road. ($10 for a 4'x'4'x5' bag)
The next boxes are about 30" off the floor, so the birds have the entire floor except for space taken by the waterer and feeder.
The bedding is now about 6" deep, no smells, no mess - clean & dry - it's fantastic!
I thought of putting 8" boards at the doors, but haven't got around to it - we just kick any litter out of the way as we walk in - and some falls into the coop - not the end of the world.
The only issue we're having is dust - from the feed perhaps? We need to heat in the winter, and dust buildup will be a fire hazard.
Will start misting the coop every now and then to see if that helps.
Have a great week!