How long should a liner last in an above ground swimming pool

Liners for above ground pools don’t last as long as most people think. Forget about what the salesman told you when you were buying the pool or what the internet guy said before he talked you into buying his pool or liner.

Let me set your expectations to a lower and more accurate level so you can be happier with what you bought and what you have.

Good quality standard gauge (20ga or mil) above ground pool liners will realistically last an average of 3-5 years. Heavy gauge liners (25ga or mil) will average 5-8 years before needing to be replaced. This is based on liners made in North America and are fully printed(print everywhere).

FIVE FACTORS THAT MAY DETERMINE HOW LONG AN ABOVE GROUND POOL LINER WILL LAST

Over the thirty-plus years of installing and working on above ground pools, I have tried to observe and understand why some liners will last longer than others. In truth, I haven’t come up with much, but this is what I’ve seen.

1 Chemical balance and maintenance

It’s not always the case, but most liners will last longer in pools that were chemically maintained well.

I gather feedback from people when I’m changing their liners and will ask them how they take care of their pools chemically. It’s hard to determine as everyone has their own way of maintaining a pool, but pool owners who are more diligent in keeping the pool balanced tend to have longer-lasting liners.

2 Direct sunlight

This may only pertain to areas with harsher sunlight and longer hot seasons, but at least here in Central Florida, the more direct sunlight a liner gets, the quicker it deteriorates.

Above grounds that are often covered or are under a canopy of trees or are screen enclosed will have liners that fade less and last longer. Again, this isn’t always the case, but direct sunlight is hard on everything. Even if it’s underwater.

3 A lot of surface rust on the inside of the pool’s wall

When replacing a liner, it’s always best to address the surface rust on the inside of the pool’s wall (if it has any). This is mainly because the rusty wall will take some life from the new liner as it will be pressed up against it.

Note: If you’re replacing the liner and notice a lot of surface wall rust, you can purchase wall foam and apply it to protect the new liner from the rusty wall.

4 The PH of the earth (theoretical only)

I have never been able to verify this, but some will say that if the earth the liner is resting on is too alkaline (high ph), then the liner will prematurely deteriorate.

I cannot prove it but this may be a real thing. I say this because some above ground pools will have liners that only last a couple of years. It’s rare, but some people will call me every couple of years to replace their liner.

I’m always curious when liners don’t last long in certain pools. I’ll ask all questions about how they chemically treat their pool, what kind of usage does it get, do they let it get green often, and so on.

Some worn liners will appear to be prematurely brittle on the bottom piece and that’s what makes me wonder if something in the ground is causing this. In reality, it’s hard for me to conclude this for a few reasons that I have observed over the years. Still though, it, like most things, is at least possible.

5 The pool turned green often

I have noticed that liners sometimes don’t last as long when the pool turned green often. This isn’t the normal condition of some people struggling ( and often failing) with keeping their pool clear. It’s more of the pool owners who are either gone a lot or just don’t care and let the pool go regularly.

Some above ground pool owners in the warmer states will just let their pools go in the winter months. The cooler temperatures don’t make the water freeze, so pools don’t need to be closed but people will just stop adding chemicals and running the filter. The result is less cost to them in the winter but the pool gets green or worse and then they bring it back to clear every spring just before swim season. I don’t recommend doing this, by the way.

I cannot explain how an above ground pool turning green regularly takes life from its liner. I can tell you that it does though.

TYPICAL ABOVE GROUND POOL LINER WARRANTIES ARE FOR 15 AND 25 YEARS LONG

When you see that a liner warranty has a 25-year length to it, it’s natural to think that it should last at least 20 years or so. Yeah, nope! Not even close.

Warranties are great for some things that you buy. Cars and higher-end electronics have great warranties that can really make you feel secure with the purchase and give you a good estimation on how long what you bought will last before giving you problems. Above ground pool liners are not on this list.
The reality of an above ground pool liner warranty’s duration and how long it will actually last is the following:

LINER TYPE WARRANTY. AVERAGE LIFESPAN

Note: Old school Doughboy liners made by Latham are the best, longest-lasting liners, but they cost 2-3 times more than an average liner.

Note: Liners made in China are very poor and don’t last long. Make sure you are not getting one of these.

WHAT’S THE DIFFERENCE BETWEEN 20/25GA AND 20/25MIL ABOVE GROUND POOL LINERS?

When shopping for a liner for your pool, you’ll come across descriptions of both mil and ga. Many ask me what is the difference between the two. Here’s the short answer – “nothing”.

First off, both ga(short for gauge) and mil are measured units for thickness, but not for pool liners. You will commonly see gauge used to describe how thick a wire is, and you will commonly see mil to describe how thick plastic sheeting is.

For liners though, ga and mil are just a marketing description and not a unit of thickness. What you need to know here is that the higher the number means the heavier the liner, which means it was made with more material.

So, a 25ga or mil liner is heavier and should last longer than a 20ga or mil liner. There is absolutely no difference between a ga and mil.

20GA/MIL VERSUS 25GA/MIL WHAT DOES THE NUMBER MEAN?

Typically, you will see liners described as 20 or 35 gauge or mil. The 20 usually means standard gauge and the 25 means heavy gauge. The ones with 25 on the description will usually be $20 to $100 more than the “20” ones depending on the liner size. And they are usually worth the extra money as they will last longer.

When looking to buy a liner, you might come across a higher number than 25 in the description. I have seen 30, 35, and 40 mil and ga named liners. This may mean that the liner is heavier or better than a 25ga/mil liner, but usually not. It’s usually just a marketing ploy to get you to think you are buying a better liner.

There are some custom made liners that are heavier than a normal heavy gauge liner. It’s best to verify this with the retailer. As a pool installer, I’ve seen my share of liners that say 30 on the box, but are no heavier than a 25.

WHICH LINER WOULD I BUY FOR MY POOL?

I think it’s a common want to get the liner that will last the longest. This is what I would want and do. So, I would get a fully printed, heavy gauge(25mil/ga), uni-bead/j-hook liner that is absolutely made in North America.

You might have thought that I would buy the expensive Latham liner made for old school Doughboy pools as they last the longest. In truth, I would prefer one of those but cannot trust actually getting one. Latham now makes regular liners and most Doughboys now come without this expensive liner. So it may be hard to verify if you are getting one of these. Plus, for me, the Latham liner is really expensive and I’m not sure it’s worth it against how long a less expensive quality liner can last.

NOTE: Almost all expandable type liners only come in standard(20) gauge. Heavy gauge expandables usually have to be custom ordered