I have read all the top ranking blog posts and all the forum comments about pool liner thickness, and quite frankly they only know part of the story. I wrote a pool liner review five or six years ago, and it looks like a lot of these websites are paraphrasing and rewording my article to some degree.
Pool Liner thickness is described differently for in-ground and above-ground swimming pools. If your an above-ground pool person, read the in-ground part too, it will give you some perspective.
In-ground Pools – Pool Liner Thickness
Fact – The thickest inground pool liner is 27 mil. Not including that 60 mil stuff that has been coming around the last three years, where they cut and weld the stuff right in the swimming pool.
It does not matter if mil is an actual measurement! With the in-ground market, 27 mil is the best you can buy. If you want the best, then buy a 27 mil pool liner.
Wall and Floor Pool Liner Thickness – Yes This Is A Thing
You can buy 15 mil, 17mil, 20mil and 27 mil material for an in-ground pool. You can by a 17/17, 20/20 27/27, or any combination. The most popular is a 20/27 and 20/20, as most in-ground liner installers don’t believe you need 27 on the wall, and it is much easier to install, especially on pools with 90-degree corners. Not to mention the 20/20 weighs considerably less than a 27/27. On a 20×40 swimming pool, we are talking 100s of pounds.
Above-Ground Pool Liner Thickness
Nobody in the above-ground pool liner industry uses mils to describe pool liner thickness. If you call Latham Pools, my favorite pool liner manufacturer they will tell you over the phone. That’s more than I can say for Swimline or GLI.
Swimline and GLI Above-Ground Pool Liner Manufacturers
These guys own most of the market so I will discuss them first. They are basically the same company. GLI stands for Gary and Larry Industries (true story), and Larry owns Swimmline.
Swimline uses Perma to describe their pool liner thickness. I sell and install their Perma 2500/Perma 25 pool liners and have had no problems. Occasionally I will see Perma 30 discussed, but I don’t even know if they exist.
Latham Above-Ground Pool Liner Thickness
Latham calls their thickest liners HG which stands for heavy gauge. Kill me now! But their HG liners are the thickest I have ever handled. I warn everyone who buys a Brighton Prism HG liner from me. You have to install it on a sunny day with the temperature above 70 degrees. I also recommend it be installed by someone with experience installing thicker pool liners.
Still, we get calls from people who say: “I think you sold me the wrong size pool liner, my pool walls are buckling”. Yeah, no shit, I told you this was a thick ass pool liner when you bought it. Now pump the water out so your walls will straighten back up and wait for a sunny day.
Can you imagine if anyone ever tried to install a 27mil liner on an above-ground pool wall? Forget about it, the pool would be destroyed.
Gauge and Pool Liner Thickness
Pool Liner World is selling 25 gauge pool liners. What does that even mean? Not even the manufacturers are this vague. Pool Liner World are clearly selling Swimline/GLI liners, does this mean they are Perma 25? Maybe Perma 20? Who knows because there is no basis for this term.
I understand HG; I even understand Perma because the manufacturer uses it. In all fairness In The Swim is describing their pool liner thickness the same way. But if you compare a 24×52 beaded liner. In The Swim’s website sells a 20 gauge for the same price that Pool Liner World sells a 25 gauge. But In the Swim also sells a 25 gauge, and it cost more which makes sense if you’re buying a thicker pool liner.
I believe that In The Swim is translating Perma into gauge while Pool Liner World is not. Doesn’t matter to me, I sell a Perma 2500 much cheaper than either of them.
I Am No Pool Liner Dealer / Distributor
I only buy swimming pool liners to put in the above-ground pool packages I sell. I only sell pool liners with a 52-inch wall height because I only sell pools with a 52″-pool wall. Selling the liners seperately helps me to order larger quantities and get my price down. But if you happen to have a swimming pool the same size as the ones I sell, I could probably give you a good deal on a pool liner.
It pisses me off to see people spend good money and end up putting a pretty trashbag in their pool. Yeah, I said it, trashbag! I don’t have a huge inventory and can only help so many people as I have to have liners available for my pool packages. But hopefully, if enough people start using my online pool store I will be able to stock a larger and more diverse selection.