I've been feeding a feral cat that comes to my back door every evening. I was worried a few days ago because it was getting extremely cold at night, way below freezing. I googled it and learned how to make a shelter from a yard-long Rubbermaid box from WalMart, with two-inch thick styrofoam walls, floor and ceiling from Hobby Lobby, straw from Westlakes, and Mylar from a space blanket taped to all the six surfaces. Paper on the bottom so it wouldn't crinkle. Two doors facing each other at the top of the long sides, six inches high by four inches wide, I didn't think a grown raccoon would fit. Anyway, the cat slept inside it the night before last, there was a cat shaped hollow in the straw in the long, straw-filled room below the doors. But last night I heard a yowl, and this morning found the box pushed to the middle of the deck, it had been under the eaves against the house, the papers had been torn out, and the edge of the styrofoam inside both doors had been gnawed, I think the raccoon was trying to enlarge it to get in, but just gnawed the styrofoam, not the hard blue plastic of the tub. What can I do to make this a safe, warm place for the cat to sleep and be protected from the elements and raccoons?