Before You Begin
There are some things everyone should do before breaking ground for an above-ground pool. Most municipalities require a permit or have regulations as to fencing and positioning of swimming pools. Each area is different, so check with your building and zoning office. Another factor that should be considered is underground utilities and septic tanks. If you have any underground utilities, call the utility company and have it mark where they are. Don't install your pool over your septic tank if you have one. Also, check the weather report and make sure you have a few dry days coming to install your pool. It can get pretty messy while digging up the sod and leveling the ground if it's raining.
Preparing the Ground
This is the most difficult part of the installation process. You must always dig to the lowest level of ground and never fill the low level up. You'll be dealing with tons of water, and the pool could collapse if the fill does not hold. In some cases, actual retaining walls can be built to hold fill dirt for pools, but that should be done by a professional for safety. The ground must be cleared and leveled. All rocks, twigs, root and stones must be removed from the pool area or the liner could become damaged. The ground is level when a long 2-by-4 board is placed across it and a carpenter's level is placed on top. When the bubble lines up in the center, the ground is level. You can move the board around to different places to ensure the entire area is level.
Putting Up the Pool Walls
Patio block is used as a foundation for each of the wall posts. The blocks must also be leveled, not only individually but from block to block. The size and amount of wall posts will be different, depending on the shape and size of the pool. The track and bases for each of the wall posts are then set, making sure each wall post will sit totally on the block. Clean masonry sand is then placed in the center of the pool area. There should be enough sand to cover the area 2 inches deep. It can be raked out and then tamped down to make it firm and smooth. This will be a buffer for your liner for anything that goes on in the ground after your pool is up. The next step is to install the pool walls. The wall is unrolled into the track and screwed together at the seam. It helps to have many helpers with this part, because it doesn't take much to knock over or blow down the walls. After the screws have been put in place, duct tape should be placed over them so they do not touch the liner. At this point, a grass killer can be put on the sand and wet with a hose sprayer. Tamp the sand again to keep it smooth.
Installing the Liner
Build a cove around inside the pool where the sand meets the liner. You can use a cove material or build it up with sand. This keeps the liner from getting pushed into the crack at the bottom of the wall and tearing. The liner is installed next. This must be done slowly, making sure there are very few wrinkles. Once it is unfolded and pulled up the sides, you can use clothespins to hold it up while you are filling it with water. This is an easy way to make adjustments as the water stretches the liner. After about 1 inch of water in the bottom, you can smooth most of any remaining wrinkles; by 2 inches you will probably not be able to move it any more. Once the pool is filled to below where the skimmer and intake hose will be installed, the top rail can go on. It will hold the liner in place while the posts are being installed. The liner should be pulled tight up to the top rail. The plumb and level of the posts should be checked as each one is installed, and the screws shouldn't be tightened until all of the posts are installed. The plumb and level should be checked again, and screws can be tightened.
Installing the Filtering System
Installing the filtering system will require cutting the liner, so great care must be taken here. A template will have been supplied by the manufacturer of the pool, and a good silicone sealer is a must. Follow the manufacturer's directions when installing the filtering system, as any deviation can void your warranty. You should also have a licensed electrician hook up the pump and run the wire to the pool, as this can be very dangerous and even deadly if not done correctly.