Some of the coops have 1" x 2" welded wire under the roosts and some of the other coops have 2" x 4" welded wire under their roosts. The coops that have the smaller welded wire in them, I use mostly as grow-out coops. The permineter of all of my pens are chicken wire but with the electric wire around them, nothing tries to get in because if it touches the wire it will get a good shock. When I touch the wire my heart will skip a few beats. The inside wire between the pens is 5' 2" x 4" welded wire with 2' chicken wire around the bottom so if the males want to fight they can't get their heads through the wire.