Most of the time soft side water beds can be placed upon your old water bed drawer pedestal.
Worries of damaging the pedestal due to weight should not be of concern because they weigh 20-25% less than a hard side water bed. If you don’t have drawers from an old water bed adding additional storage space to your bedroom is easy. There are many companies that make storage systems for mattress and boxsprings that are strong enough to support the more conventional looking softside water beds. These conventional drawer pedestals work well at utilizing unused space normally only taken up by the mattress set. One such brand is Furniture Traditions who makes a platform bed pedestal. Another brand is Seahawk Designs Sto Away Drawer Foundations. Both will accommodate a soft side waterbed mattress. There are other brands that will do this so if you are not sure ask the retailer or go to the pedestal manufacturer.
Softside waterbeds can be used with and without foundation on The Furniture Traditions drawer pedestals which for example are available in two heights 9” or 14”. The final overall height you want will determine whether or not you use the 9”softsid foundation. Overall height of pedestal and mattress can range from 18” high up to about 36” high. Pedestals generally range from 9” to 18” high. This height would be added to the height of your mattress and foundation which usually run from 18” to 21” high. A softside water mattress only usually runs from 9” to 11” tall.
The major consideration in determining the proper height of the whole bed is that it will not hide the headboard you are setting it in front of. Many drawer pedestals come with a platform which has a 1 ½ -3” trim or boarder around it. If you do not have a platform you can use 7/16” OSB or plywood on top of the Pedestal. We determine the outside length and width of the mattress set and then cut the OSB about 2” short of the length and width of the mattress. Next we screw it down to the top of the pedestal so it forms a stable platform for the waterbed mattress and or foundation. Under sizing it will keep the rough edges from being seen when the mattress is set on it. A conventional spring mattress could be placed on your waterbed pedestal as well. If it moves around on the top of the platform place several large pieces of rubberized shelf liner under you mattress to stabilize the mattress so that it will not move.
The moral of the story is don’t be too hasty in getting rid of your old waterbed drawers. They might have a second chance at life by being recycled through reuse.