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Made in USA Inground Pool Liners
Should you use 20, 27, or 30 mil vinyl?
Liner walls
Use heavier vinyl when possible
If at all possible, it's always a good idea to use 27 or 30 mil vinyl on the walls. The walls are the area of a liner that normally receives the most wear and tear, especially above the waterline and in the corners above the waterline.
Vinyl above the waterline is exposed to the most solar radiation due to direct exposure and reflection off of the water's surface. Another way to protect this vulnerable portion of the liner is to use Ameri-Shield to block direct exposure to the sun's damaging rays.
Liner floors
Consider the pool base
If the floor of the pool is vermiculite, Pool-Krete, or another smooth composition base, a 20 mil floor is a good selection.
If the floor of your pool is sand, concrete, or another highly abrasive surface, a 27 or 30 mil floor is recommended. A heavier liner is a bit more expensive and somewhat harder to install, but it is still better than having to replace the liner prematurely due to failure.
More info
Mil and gauge are not the same thing
Want to learn more about liner thickness? Our Pool Liner Thickness page explains the difference between two commonly used vinyl standards, gauge and mil.