This above-ground pool is a great idea, especially if you have young kids. It’s made by Zodiac, the well-known French manufacturer of high-end inflatable watercraft. It features high-tech materials and great engineering, but the idea is about as simple as they come: a very, very big inner tube with a bottom attached. Every surface is soft and forgiving. There are no metal parts or sharp corners inside or out that can cause injuries. And, because the side-wall tube is so wide, kids can run around it and jump into the pool from anywhere they want. The older crowd can sit on the sides and dangle their feet in the water, or lie back and sunbathe in comfort. No extra perimeter decking is required.
This side-wall tube can functions as a deck because it’s so firm. A 160-pound adult walking along the top barely depresses the surface. This firmness is the result of the system used to fill the pool with water. As you’ll see later, there are two holes in the inside surface of the tube that must be plugged with removable discs before you start inflating it with air. Once the sides are inflated, you fill the pool with water and then you remove the discs that separate the air-filled tube from the water-filled pool. Water immediately rushes into the side walls. Because air is a gas and can be compressed, the water keeps filling the sides until the air is so compressed that it won’t let in any more water. At this point, the side-wall tube is nearly rock hard and can support anyone who walks on it.
Another great, kid-friendly feature of this pool is its floating skimmer. Usually the skimmer is fixed to the side of the pool and the water level inside the pool must remain at the skimmer height for the circulation system to work properly. Because this skimmer floats on the surface of the water, you can adjust the water level to suit the height of your children. When they’re small, you can keep the water level low. As they mature, you can raise the level.
The pool model we installed is called the Ovline 3000. Its oval shape measures about 30 ft. from end to end and 21 ft. across. Its internal swimming area is about 24 ft. long x 12 ft. wide, with a maximum water depth of 4 ft. This pool costs about $6500, including the pump, filter, skimmer, an underwater repair kit and the ladder shown. Zodiac has many other pools ranging in size from the 12-ft.-dia. Toopy wading pool ($800), up to a huge 55-ft.-long x 27-ft.-wide rectangular model called the Hippo 65 ($11,000) that can be special ordered.
All in all, this pool design has a lot going for it. It’s even easy to install. If we had to do it again, two of us could finish the entire project in one day. There were, however, some glitches that made things harder than they had to by had to be. First, the manufacturer’s installation directions were astonishingly incomplete. (Zodiac says they’ll be working on better directions soon.) And, an important part, an adapter for hooking a standard shop vacuum hose to the inflation port, was missing. A lot of time was wasted cobbling something else together. It’s also fair to say that the company could have been more responsive. Phone calls, letters and e-mail almost always languished in the ether. Fortunately, dealing with the national distributor, Comfaire Products (144 Nugget Dr, Charlton, MA 01507) was much more rewarding. Both Zodiac and Comfaire can be reached at the manufacturer's website, www.zodiac.com.
(Editor's Note: while this product information dates to 2001, the process of installing a pool is still useful if you're using another model.)
This project was originally published in the May 2001 issue of Popular Mechanics. You can find more great projects at Popular Mechanics DIY Central.
Step 1: Locating the Pool
The first thing you have to do is select a good location for the pool. Because it must be installed on a flat, level surface, the closer your site is to this goal, the less preparation work you'll have to do. Of course, if you're lucky enough to have a flat, level surface that can accommodate the pool, all you'll have to do is remove any stones that you can feel as you walk barefoot over the area, then lay down a tarp over the grass, and you’re ready for the pool. We weren’t so lucky.
Our site was about 2 in. lower on one end than the other and just over 3 in. out of l level from side to side. To remedy this, we created a 3-ft.-wide level berm of topsoil around the perimeter of the site. Then, we removed any stones from the interior and brought in enough sand to make the area level within the berm. In our case, this took about 6 cubic yards of sand. Once the sand was in place we raked it smooth (Photo 1), then leveled it using a screed board.
Two of us used a 16-ft.-long 2 x 4 to do this. We held one end of the screed board at the center point of the site and dragged the other end around the entire perimeter, trying to maintain a level board as we worked. Sometimes the sand was too deep to move the board easily, so we made several shallower passes until we achieved a level base.
Once you’re satisfied that the base is level, compact it with a lawn roller (Photo 2). Make several passes from different directions and recheck the level when you’re done. Make any necessary adjustments, then cover the sand with a tarp (Photo 3). Smooth out any wrinkles in the surface, and drive several landscaping spikes through the grommets on each side of the tarp to keep it from moving when you are installing the pool.
Step 2: Pool in a Box
It’s hard to believe that a pool this size can come in a 2 x 3 x 6-ft. box that weighs about 280 pounds.
You’ll need some help, but it’s easy for a couple of people to handle this box with a hand truck. Roll the box to the middle of the tarp, remove the cardboard and the small parts that are included, and then unfold the pool lining (Photo). Center it on the tarp and smooth out any wrinkles in the bottom.
There are two holes in one end of the pool that are outfitted with plastic pipe nipples. One nipple is attached to a hose that runs through the tube wall and connects to another nipple on the inside of the pool - this is where the skimmer will be attached. The other hole simply goes through the side-wall material and into the tube cavity. The water circulates through this system by first being drawn into the skimmer, then through the interior hose and onto the circulating pump. This is called the intake side. The pump sends the water through the filter and then returns it to the pool through the nipple that goes into the tube cavity. This is called the return side. The filtered water in the tube cavity circulates to the other end of the pool and goes through the two circulation holes located there into the interior of the pool. To control this flow and isolate the pump and filter for service, both nipples are outfitted with large ball valves.
Step 3: Pool Plumbing
To install these valves, first cover the threads with Teflon tape. (The manufacturer suggests 15 turns of tape for each joint.) Then slide the valve’s tightening nut over the nipple and thread one side of the valve fitting onto the nipple (Photo 1). Attach a hose adapter to the other end of the valve body, then join the valve to the nipple with the tightening nut (Photo 2). Snug the nut in place with large pliers. Do the same to the other nipple. Make sure both valves are in the closed position.
Next, go to the opposite end of the pool and find the two circulation holes located near the bottom of the inside surface of the tube. Install the two closing discs in these holes (Photo 3). These discs prevent air from leaking out when the tube is inflated. They will be removed later when the pool is filled with water. Taking them out then is easy because they are attached to flotation discs with cords. Just make sure to install the discs so the cords are on the bottom.
Step 4: Inflating the Pool
Once the valves and discs are in place, open the inflating hole and attach a shop vacuum hose to it (Photo 8). As mentioned earlier, not having the proper fitting to do this was an aggravation, but duct tape saved the day. It takes a while to inflate the side-wall tube, about 1 hour in our case. While it’s taking shape, pull out any kinks or folds that may appear (Photo).
As the pool inflates and takes shape you can move it if necessary to achieve the proper location. Once the tube is full of air, shut off the shop vacuum and screw the sealing cap onto the inflating hole.
Step 5: Attaching the Skimmer
Next, move to the inside of the pool and apply Teflon tape to the skimmer nipple (Photo 1) and thread the skimmer adapter into place (Photo 1). Hand tighten this fitting, then snug it with pliers and install a hose adapter fitting in the other end (Photo 2). Now, slide the hose that’s attached to the bottom of the skimmer onto this hose adapter and attach it with one of the snap connectors supplied with the pool package (Photo 3).
To work properly, this skimmer hose will have to be adjusted after the pool is full of water. All that’s required is moving a plastic strap on the hose to form a loop that looks something like a plumbing sink trap. When adjusted properly, this loop keeps the skimmer floating in a level position instead of tipping from side to side.
Step 6: Installing Pump and Filter
Move back to the outside of the pool and, using hose clamps, attach a hose between the intake valve (Photo 1) and the intake port of the circulating pump (Photo 2). Install a hose adapter to the return port of the pump (Photo 3). Then run a hose from this adapter (Photo 4) to the top of the filter (Photo 5). Complete the circulation path by running a hose from the bottom of the filter (Photo 6) to the return valve on the end of the pool.
Step 7: Add Water
At this point the pool installation is nearly complete and it’s time to start adding water. In our case this took about 8 hours. When the water reaches a height of 42 in., turn it off and pull out the closing discs that have prevented the water from flowing into the tube sides (Photo 1).
Immediately, the water will start rushing into the side-wall cavity and start forcing out some of the air. This air will bubble to the surface of the water and shake the pool, sometimes pretty violently. But after a while (in our case about 30 minutes), the bubbles were gone, the water was calm and the top of the cavity wall was very hard due to the compressed air. Because much of the water that was inside the pool is now inside the wall cavity, you’ll need to add more water to fill the pool.
At this point you should open the intake and return valves on the end of the pool, and plug in the circulating pump and switch it on. Check all the hose connections for leaks, and tighten any fittings that are loose. Then, take about 1 quart of pool water in a clean container to your local pool supplier and have the people there test it and suggest a treatment plan that fits your needs.
We finished up this installation by spreading a little No. 1 crushed stone around the perimeter of the pool to discourage plant growth (Photo 2). We then planted grass seed on any bare lawn spots and assembled and installed the ladder that came with the pool.
Now you're set to enjoy the summer heat from the comfort of your back yard.