Mine have a Pighouse (the DC old playhouse) like a little wooden Swiss chalet.
It is so much easier and nicer for the Cavy Slave too, cleaning the hutch in a shed than in the open. Have they got a running about area on the floor? Tunnels and boxes to play in, make a Guinea Village.
We use big cardboard sheets behind the hutches in our Pighouse and that insulation roll in the bis they can't gnaw.
Our pigs have taken over the 8x6ft play house for the winter. Their 6x2ft hutch is along the side and then we have put lino across the floor. With steps to help then in/out. The floor is then covered in piles of straw, boxes, tubes. They have open access all day and loving it.