My piggies live in my shed. They have a hutch in the shed which is constantly open. I have newspaper and hay in the hutch itself (so they’ve always got something to forage through and eat) but fleece on the shed floor (with a waterproof layer down first, then an absorbent layer, then the fleece on top). I can only do this in summer though as I have found that using fleece outside in winter means that it doesn’t dry properly.