As I say, I add extra larger plywood to base, I glue down with silicone adhesive to avoid holes. The carpet is over pressboard so moisture is the enemy. I use several in covered outdoor cat kennels that are roofed with exposed sides (when weather dry. With rain, I add tarps to sides). I usually buy the wider base models, this is my first one of this model. It is ok but a bit top heavy. My base removes that problem, but most people wouldn't bother to add base. Great value for size, decently made. I do prefer wider base models. Wanted to try this one. I can report more later. So far so good.