Thanks for all that info.
I let them out yesterday for the first time, about 1pm, big mistake. As you say, they have very little awareness to danger once they're in the zone with finding food. I got 2 back with rolled oats in a bowl and had to grab the other 2 and put them back in. As mentioned and suggested by my neighbour, I will let them out close to sunset so they, hopefully, go home on their own.
I put a mesh floor in the shed and it's raised about 500mm off the ground on stumps. The deep litter sounds great and I might get some of that ply that's sealed for construction and cover the half they roost over which would leave plenty of ventilation.
I'll get some pics. You may all wonder where the money went but just galvanised fittings alone cost a fair bit.
