Since we've been having problems sharing the hayloft lately, I'm adding a second hay area upstairs. The grids used along the back and for the hay rooms upstairs are a soft plastic. They were chosen in hopes that the smaller holes would prevent a lot of hay from being pushed out of the cage because I'm constantly cleaning up along the floor at the back of the cage. Since those grids are of a soft plastic, the coroplast along the back of the cage and in the hay rooms will be higher to prevent the pigs from chewing up the plastic.