wow, there's a lot of info on this thread. i learned some new things, like my roost is too close to the wall! i was planning on using hay to line the 2 short mesh walls of the run area underneath my coop (the run is built against my garage). i was thinking that this would work like insulating the coop's "basement" while giving them a sheltered area outside, and would compost when i was done with it. but i'm reading people are concerned about using hay? i'd rather not do plastic if i can help it, but should i skip the hay?