;There are several reasons why some landlords will not permit the installation of waterbeds. First, there is a weight issue to consider. A king-size California waterbed can weight up to 2000 pounds, which can put a significant strain on floor joists. There is also the possibility of a catastrophic mattress failure, which would cause the same kind of water damage as a burst pipe or a leaking water heater. The logistics of filling and/or emptying a waterbed may also be an issue for some landlords.