The thickness of a vinyl pool liner is critical to how the liner fits. To work properly, a pool liner needs to have a good balance of different properties. Imagine a gymnast, that needs a balance of strength, flexibility and size. Vinyl liners are similar. The liner needs to be strong and flexible but not too thick or heavy.
At Tara we recommend a 20mil thickness because it possesses this perfect balance. A 20mil liner has more than enough strength to bear the weight of the water. It is flexible enough to fit in tight corners and intricate shapes. But unlike thicker liners, it is not too heavy or bulky.
Although, 27, 30 even 40mil liners are available, we do not recommend using anything thicker than 20mil. A thicker liner may not conform to the shape as well. Because it is often stiffer, a 27ml liner may not fit securely in tight corners. This is like asking a weight lifter to bend into a pretzel shape.
A 20mil liner will give a snug fit, so it won’t have to overstretch. That is why many liners fail. They are overstretched either because they don’t fit properly or they are too thick to conform to the shape of the pool. If the liner is overstretched above the waterline it weakens and pulls away from the walls and will be more prone to UV damage. Don’t be fooled by thinking thicker is better!