Above ground swimming pool liners are made of a thin vinyl material, and are designed to hold water in your above ground pool. The water inside an above ground pool pushes out against the pool walls and actually holds the walls up. If all of the water is drained from the pool liner, the thin steel pool walls will collapse inwards and be damaged. Swimming pool liners are a functional part of the above ground pool, but also add style and character. Above ground pool liners are available in an amazing selection of attractive patterns and styles, and often set the dcor for the entire swimming pool area.

Replacement swimming pool liners for above ground swimming pools can be found in several grades, or thicknesses. The thickness of vinyl pool liner material indicates how durable the pool liner is, and how long it might last inside a swimming pool. The thicker the pool liner material is, the more durable it will be. The measure of pool liner thickness is presented in either gauge or mil, both meaning the same thing. The pool liner included with most new above ground swimming pools is plain blue color, and a 20-gauge thickness. Replacement swimming pool liners can be found in thicknesses up to 30-gauge.

Above ground swimming pools are built to accommodate either an overlap style liner, or a beaded style liner. The difference between a "beaded" style liner, and an "overlap" style liner is the way the liner is held in place inside the swimming pool. Beaded above ground pool liners have a very small groove or lip at the top edge of the liner. This small lip is snapped into a track all the way around the inside of the swimming pool at the very top of the pool wall, to hold the pool liner in place. If your swimming pool requires a beaded pool liner, you will be able to see this track by looking under the top rail on the inside of the above ground swimming pool.

An overlap style pool liner is folded over the wall of the swimming pool, and held in place underneath the top rail of the above ground swimming pool. If your swimming pool requires an overlap style liner, you can see a small amount of the pool liner under the top rail on the outside of the swimming pool. To install an overlap pool liner the top rail of the above ground pool is removed all the way around the pool. The new liner is placed in the pool, and draped over the top of the thin metal wall of the pool. Long plastic clips are placed over the liner and the thin metal wall to hold the liner in place, and the top rails are re-installed over the new liner. Most of the excess liner hanging down on the outside of the pool can be trimmed off.