People often associate a swimming pool liner with an above-ground pool rather than an in-ground pool because it is a vinyl membrane that separates water from the pool structure. The liner functions as a shield against algae and corrosion. Traditionally, an in-ground pool relied on concrete or fiberglass as a protective liner. Today almost 70 percent of U.S. residential pools use vinyl liners, according to SwimmingPoolsetc.com. Vinyl gained popularity because it is cheaper and easier to maintain than traditional materials.
A swimming pool liner comes in three forms: overlap, beaded or unibead liner. An overlap liner ranks among the most popular for above-ground pools. The liner overlaps the top edge of the pool, drapes down the side and stays in place with plastic clips. The beaded liner fits both in-ground and above-ground pools. It snaps into a bead receiver, which is a concealed track that goes around the rim of the pool. The unibead liner is also called a J-hook liner because it has a perforated edge that looks like an upside down letter J. The unibead liner fits above-ground pools only, but it works as an overlap or a beaded liner. Some swimming pool owners hang the hooked edge over the pool wall like an overlap liner. Other pool owners tear off the perforated portion and use it as a beaded liner.
You can distinguish between swimming pool liners by the finish at the top of the pool. A rail covers the area where an overlap liner attaches to the pool. A portion of the overlap liner remains visible even after it is trimmed. A beaded liner creates a clean connection between the pool wall and the top of the pool. A unibead liner acts like an overlap or beaded liner, so it can be more difficult to identify. However, a unibead liner always consists of 25-gauge vinyl as opposed to other liners that are available in 20- or 30-gauge vinyl. Otherwise, swimming pool liner types are similar. They come in a variety of prints and colors. The most popular shades are blue and green. Most liner types measure 48, 52 or 54 inches in height.
Istallation Time Frame
Installing a liner for an in-ground pool takes one to two days. Contractors place the liner in the pool then attach vacuums to pull the liner toward the walls. The average liner lasts 10 to 15 years before needing replacement. Liner replacement takes longer because the process is labor intensive. Contractors measure the swimming pool for an accurate fit. Custom orders take two to three weeks to ship. Upon arrival, contractors tear down the old liner, repair walls and remove and level any contaminated sand beneath the pool. By comparison, a liner goes into an above ground pool much more quickly. Installation times vary depending on whether you have the liner professionally installed or not.
Some liners fit a pool better than others. Go with the liner that your swimming pool manufacturer recommends. If your pool accepts a variety of liners, weigh the costs and benefits of each type of liner. The beaded liner holds an advantage over other types of liners because you sometimes avoid the cost of a total overhaul. When there is a hole at the bottom of the pool, just switch out the lower portion. You do not need to replace coping or other parts at the top of the pool. A beaded liner also blends into the border pattern. On the other hand, the overlap liner is less expensive and you can install this type of liner without a contractor. The unibead liner combines features of the beaded liner and the overlap liner. If there is a leak at the bottom, you can convert from an overlap to a beaded liner. However, the unibead liner tends to shrink and pull away from the wall. As the vinyl stretches, the lifespan of the unibead liner decreases.
Over time, a swimming pool liner loses resilience, gets punctured and begins to leak. Pool owners test for leaks by squeezing a few drops of food coloring into the water. The coloring gets sucked toward the opening. If left unchecked, leaks cause sinkholes as water seeps out and dislodges the back fill and sand that support the pool structure. You can repair leaks with a vinyl patch kit. Some wet patch kits adhere under water, so you do not need to drain the pool.