Causes of Pool Liner Wrinkles and How to Fix Them

Vinyl pools were first introduced to American homeowners in the 1950s, mainly because they were more affordable than concrete pools, which remained out of reach for many homeowners in the Northeast and Midwest, where harsh weather conditions necessitated more expensive construction. Today, they’re more sophisticated and very popular, but there’s one unsolved question: why do pool liners wrinkle?

A pool liner develops wrinkles in both above-ground and (less commonly) in-ground pools for several reasons. Chemical imbalance, poor installation, water absorption, age, and ground movement are some of the more common causes, most of which can be remedied and the wrinkles removed.

Getting wrinkles is as inevitable for vinyl pool liners as it is for people – it’s just part of the aging process. There are other reasons, too, which I’ll look at and examine what can be done to remove those wrinkles (from the pool, that is – not from the face.) Vinyl linings have made pool ownership possible for many American families, so let’s find out how easy it is to iron out these problems.

Why A Pool Liner Wrinkles

Not all the wrinkles in the pool liner are a problem, although they might be a little unsightly. However, more serious wrinkles can lead to dirt build-up in the folds, which in turn could lead to a weakening of the vinyl and a hole or tear in the lining.

The Causes Of Pool Liner Wrinkles

Some wrinkles are immediately visible in a new pool. Others appear after a time and for different reasons.

Poor Installation Of The Pool

  • If the pool lining has been made even slightly too large for the frame, it will inevitably wrinkle. With computer-assisted design (CAD) now commonly used, particularly for custom pool linings, this shouldn’t happen, but mistakes can be made. The lining must also be properly aligned and well-secured before filling the pool, or wrinkling will occur.
  • If the ground that the pool rests on hasn’t been adequately prepared, it might shift under the weight of the filled pool and move the lining.

Water Chemistry Out of Balance

If the pH level of the water is too low (below 7.2) for an extended period, the vinyl starts to absorb water and stretches, causing wrinkles to develop. Excessive chlorine or bromine in the water will have the same effect. Undissolved granular pool chemicals can also harm the liner, so pre-dissolving them is always a good idea.

Changes In The Water Table

Heavy rains might result in the ground around the pool becoming waterlogged, causing pressure on the lining and pushing it upwards and out of place. When the water table drops, the ground subsides and allows the lining to sag, forming wrinkles.

Age Of The Liner

Vinyl liners are thin but remarkably hardy and, with careful maintenance of the pool, can last up to twenty years. The average, though, for an above-ground pool is 6-10 years and slightly less for an inground pool. Those that are open all year round and exposed to daily ultra-violet rays will be most likely to deteriorate. Once wrinkles develop at this age, the only remedy is replacement.

Excessive Activity

Pools subjected to a great deal of activity, with swimmers diving, jumping, sliding, and otherwise putting stress on the liner, will most likely develop wrinkles sooner than the pool at a retirement home (where the wrinkles are on the swimmers.)

Preventing Pool Liner Wrinkles

I’ve already touched on a few preventive measures, but let’s highlight the steps you can take to minimize the risk of the liner developing wrinkles:

  1. If you’re getting a professional to install the pool, monitor progress closely. Don’t keep silent if you’re unhappy with any aspect. The base the pool will rest on is all-important, so it must be well-prepared using the right material. As the frame is constructed, it must be stable and the lining perfectly aligned and wrinkle-free from the start.
  2. As the pool starts to fill, ensure that any wrinkles are removed immediately.
  3. In an existing pool, keeping the chemical balance of the water is essential, not only for the health of the users but to protect the liner from an excess of sanitizer or water that is acidic – both these conditions will cause the vinyl to absorb water, resulting in wrinkling.
  4. If you’re in a high rainfall area with a seasonally high water table, it would be worth installing a drainage system around the pool to prevent water from getting under the liner and causing it to stretch and wrinkle when the level subsides.

Removing Pool Liner Wrinkles

Be aware that, in most cases, you will have to drain almost all the water from your pool, leaving about two inches, before tackling the problem. Some possible methods include:

Heating The Water

Using a pool heater or solar cover, heat the water to above 33⁰ F, which will help to soften the vinyl liner, which can then be smoothed out using your hands, a soft-bristled pool brush, or by sliding your feet over the wrinkles to flatten them out.

Flattening By Hand

If your pool has been largely drained, heating is unnecessary. You may be able to flatten out the wrinkles on the floor by sliding your hands over the surface and slowly moving the liner toward the perimeter of the pool. If the liner has stretched, though, you will just be relocating the wrinkles, so do this carefully.

Using A Plunger

This method does work but requires a lot of patience (and a clean toilet plunger!). By pressing gently down and then up on a wrinkle, the plunger will allow you to lift and reposition the liner sufficiently to smooth out the wrinkle or fold.

Blowing Out The Wrinkles

If all else fails, try blowing air into the space between the liner and the frame using the blower function on your shop vac. This should smooth out the wrinkles from underneath the liner. Once the air is removed or escapes naturally, the liner should remain wrinkle-free.

A Couple Of Warnings:

  • Don’t wait too long before removing the wrinkles from your pool liner; the longer they remain, the more difficult it becomes.
  • Don’t leave the pool drained for longer than absolutely necessary. Particularly with an older liner, if it dries out, it might crack or tear and require replacement. If you’re not confident of doing the job quickly, rather call in a professional.


Pool liners can last for up to twenty years, but the chances are that they will develop wrinkles during their lifetime. While these are not always a problem, they are unsightly, so I’ve highlighted why they appear and how to prevent them. If they do occur (and they probably will), I’ve also given some tips on how to remove them. Here’s wishing you (and your pool) a wrinkle-free future!