

This is my chicken pen. It was originally designed as a rabbit run and there are rabbits living in one half of it, totally separated from the chooks. Each half has a 6ft x 4ft wendy house (low level shed....4ft high) and the chicken side also has a traditional style 12 bird henhouse.

These structures all throw a little shade but I would like to add something to the roof to provide much more substantial shade and also some shelter from rain as the chickens will not shelter inside the houses in the run, but just huddle underneath the henhouse.
So....firstly, I am in the UK so will need to source these things myself but not sure what's best to use. The pen roof is flat so anything I add would not drain off when it rains. I currently have a very large tarpaulin in place but it's only been up a few weeks and is already in ribbons in places as we also get a fair bit of wind....we are at the top of a hill. I have considered corrugated plastic or steel sheeting or Onduline. I'm concerned that plastic would not hold up long term and that any sheeting would be under a lot of pressure from the wind so what would make suitable fixings? I could use wooden boards covered in roof felt.....I have several rolls of felt already....but again not sure on long term durability or wind stability.
Also, are any of these things going to be any good if that are installed flat to the current pen roof or is a slope an absolute must? If so, how do I create one on an already installed structure. And all this in a shoestring budget??
Does anyone else out there have a pen of similar design and have actual experience of this issue and how to solve it? Or any budding DIY enthusiasts with a head full of solutions? I'm after all the help I can get!
Thanks guys xxxx