Oval Pool Base

by Anita
(Hesperia, CA USA)

Hello, we are installing a 15 x 30 oval Doughboy type pool. The ground has been leveled. We are on a tight budget and are considering using some type of foam for the bottom of the pool.

I've read a lot of helpful posts describing the different types of foam but I'm still not sure about the best kind to get.

Is it better to use carpet padding or 1 1/2" styrofoam sheets? We want something that will last a long time. Would the carpet padding tend to get wet and moldy after awhile? If we use the styrofoam, what color sheets are best? In what department would I find these?

I've seen recommendations for using 1/2", 1" or 1 1/2". I'm inclined to go with the 1 1/2" but I don't want to lose too much water depth.

If the ground is pretty smooth, would an inch of sand below the pad be enough? How many cubic yards would we need for a 15 x 30? Do we need to water the sand to help pack it down before smoothing it out? Can the foam be installed while the sand is wet or should we let it dry out so the foam doesn't absorb the water?

Sorry for the multiple questions. Thank you in advance for your help.

Hi Anita. These pages might help with your oval pool installation.

Oval Pool Installation

Diamond Star Pool Installation

The most difficult part of using foam sheets with an oval pool is working around the pressure plates. Some plates are small enough in height that when covered with a little sand they don't pose much of a problem. Others, however, stick up so high the cause real problems. My favorite base for oval pools is mortar sand, it's so much easier and probably less expensive.

I would prefer foam over the carpet pad, preferably the 1 1/2" foam. Carpet pads are great if your pool sits on concrete, but that's the only time I would use them.

Either the 1" or the 1 1/2" white foam sheets would work fine. You want to just use enough sand to smooth the bottom out and possibly cover the pressure plates. Wet it down, smooth and pack. You can then work over top of the damp sand. Dry sand will shift and move a lot more than damp sand.