Mine are all in covered crates, but at the moment they are in a north facing porch which keeps cool all day long. They are soon moving into the annexe into individual dog runs, but it is a very cool building, so not a problem. You can buy coolmats, not sure where from but I have definitely seen them, I think you wet them but the dog doesn't stay wet IYSWIM. I have the cage fans for in the car, but never had to use them in the house, they are quite heavy on batteries, so use them with the cigarette lighter in the car.