In ground swimming pool liners are made of vinyl, and are available in a very wide selection of colors with attractive patterns and borders. An in ground swimming pool liner is what is called a “beaded” style liner. This means there is a small bead or lip on the top edge of the pool liner all the way around, and this small bead fits into a track that is installed around the top edge on the inside of the in ground swimming pool. An in ground swimming pool liner is designed to hold the water inside the swimming pool, which is very important to the structure of the pool. If the proper precautions are not taken, it can be dangerous to remove all of the water from an in ground swimming pool to replace the vinyl liner or make repairs. Unlike above ground swimming pool liners which can be installed by the home owner, it is suggested that you hire a local pool professional for in ground pool liner installation or repairs. Click here to find replacement in ground pool liners with free shipping.
It is very important to always keep an inground swimming pool filled to at least one foot of water in the shallow end because the earth around the swimming pool is always pushing in on the walls. The water inside the swimming pool pushes back on the walls of the pool and prevents them from caving in. Another reason to keep water in the swimming pool at all times is to combat the force of ground water pushing up from underneath. There is always water beneath the soil, and the level of this ground water fluctuates. Immediately after a heavy rain the ground water is higher, or during dry spells and in dry climates the water is much lower. If the ground water rises above where the bottom of the swimming pool is, and there is no water inside the swimming pool, the ground water will enter the pool under the pool liner and lift it up. This problem is costly to correct, and can result in damage to the pool liner.Most in ground swimming pools are built with a main drain in the floor, and contained within the main drain is a “hydrostatic relief valve”. When ground water rises to dangerous levels around the pool, this spring loaded valve opens and allows ground water to enter the main drain from underneath the swimming pool. This relieves the great pressure of water pushing in around the pool before any damage occurs. In most cases the pool filter system is running, and the dirty ground water is immediately drawn from the main drain through the pool filter before circulating back to the pool.