The Rubbermaid was my first one. They shared it for several years and then Big Bertha decided to be Bert and started flipping Scooter on to his back, in the sun, in the summertime. Now they are mostly separated. The green wooden house is the one I just built for Bert. It used to be all one pen, but now you can see the dividing wall between the two houses. I like the wooden one better and it holds the heat in well. The wooden one is about 4'x4'. I'm designing and planning to build one big one, 10-12 feet long with a divider in the middle and a door on either end. The rubbermaid sheds work, but they are too drafty and its just too much space to heat up. They don't need all that vertical space.
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