I do apologise, I wasn't clear when describing the roof, and I totally forgot the spouting for the rain-fed watering system. I will fix it up, thank you. The roof is 45cm higher on the run side than on the nestbox side, which will have a spouting and downpipe going under the coop for the chooks...
Now, I have no experience building, some planning, and I do enjoy tinkering and trying stuff out.
My coop is going to be 1.8x1.8m (6x6'), 3.24²m (36²') mobile and the run 1.8x3.6m (6x12')+ the space under the coop which gives a total of 1.8x5.4m (6x18'), 9.72²m (108²') for the run.
I'm using...