I used to put together shelters using 55 gallon Rubbermaid containers and 2 inch Styrofoam, but that became quite expensive. Recently, I learned how to make easy, inexpensive cat shelters from a great organization called Neighborhood Cats. Mine are slight variations from theirs. You can use your imagination to improve upon/change the design, as you like. Fish stores discard great Styrofoam boxes that vary in size. The ones I like to use are approximately 30" x 12" x 12". You just rinse them out, let them dry, and begin. This is an optional step: to give the shelters some weight and stability, you can attach vinyl tiles, or wooden boards (or anything else that is heavy and flat) to the top and bottom using GE Window and Door Silicone (or equivalent) and reinforcing with duct tape. If you make the top heavy enough, you won't have to place bricks on top. To cut a door, measure 2" from one side and 2" from the bottom. The door should be approx 6" x 5 1/2 ". Then you cut two pieces of 2" Styrofoam approx 12" long and 6" wide for the legs. Attach them to the bottom with GE Window and Door Silicone (or equivalent). Some web sites recommend making one side higher than the other and drilling a hole in the one (lower) corner to allow any water to drain. Another alternative is to keep the legs level, but to drill a couple of holes in the bottom so water can escape. You can line the containers with Mylar if you like for added insulation, but it's not necessary (especially if you have ...
