We have converted our basement into a 12' x 22' gameroom. The floor is painted cement. There are no appreciable cracks or significant problems. We are hearing conflicting stories about the padding necessary. Some say rubber some not. The carpet will be Berber type.
Answer:
I would put the carpet down with no underpad what so ever. I know you lose the warranty that way but if you get it soaked for no mattere what reason, the underpad is toast.