What Size Pool Pillow Do I Need? (Find Out Now!)

Jessica Stone
by Jessica Stone

With shorter days and brisk temperatures upon is, it may be time to prep your pool for the winter. If you own a pool and live in an area that experiences below-freezing temperatures during winter, you are probably very familiar with the process of closing a pool for the season. However, you may not be as familiar with pool air pillows.

These air pools have quickly become an essential component to the winterization process, as they help protect your pool walls during these harsher months. But, how do you know what size pool pillow to get? The three most common pool pillow sizes are 4’ by 5’, 4’ by 8’, and 4’ by 15’. What size pool pillow you need will depend on the size and shape of your pool.

That said, let’s take a deeper look at what pool pillows are, how to know whether or not your pool needs one, what size is appropriate for your pool, and more.

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What Are Pool Pillows?

Unless you live somewhere that stays warm for most, if not all, of the year, the large majority of pools must be winterized to some extent. This process will need to occur whether you have an above-ground or an inground pool. Although winterizing a pool is often a pretty simple process, many homeowners have to go through a bit of trial and error when it comes to covering their pool and preventing ice buildup.

This is where pool pillows come in, as they play a crucial role in ensuring that your pool is ready for winter. A pool pillow is essentially a high-gauge vinyl inflatable floating bolster that keeps a gap between your pool cover and the water, while also protecting the cover from potential ice damage. They are most commonly used with above-ground pools.

The pool pillow is installed at the center of the pool prior to placing the pool cover on top, thus, preventing the pool from sinking in the center. As your pool freezes in the winter, ice will naturally expand to the pool’s outer edges. This ultimately puts strain on the sides of your pool and can possibly cause damage. However, when you have a pool pillow situated under your cover, the empty space it creates allows the ice to expand inward instead of outward.

This means that the pillow is basically acting as an ice compensator, absorbing the constant expansion of ice. It also acts as a tent, keeping leaves, snow, rain at the pool’s outer edges where you can easily reach and remove unwelcome debris.

Do I Need Pool Pillows?

There are some pool installers that do not advise purchasing pool air pillows, claiming that they don’t offer additional advantages. However, if you live in a frosty climate, pool pillows are a vital part of winterizing above-ground pools. Without the presence of a pool pillow, ice will continue to expand and put pressure on the outer walls of the pool. This can result in damage to the sides, the liner, and the pool cover.

So, if you’re not sure whether or not you need a pool pillow, ask yourself the following two questions:

  • Do you have an above-ground pool?
  • Do you live in a region that experiences temperatures below freezing in the winter?

If you answer yes to both of the aforementioned questions, you should definitely add a pool pillow to your winterization routine.

What Size Pool Pillow Do I Need?

The most common sizes for pool pillows are 4-feet by 5-feet, 4-feet by eight-feet, and four-feet by fifteen-feet. Regardless of what type of pool you have, one of these three sizes should work. For most above-ground pools, whether it’s oval or round, a single appropriately sized pool pillow should be sufficient.

The following table provides a breakdown of the recommended pool pillow size based on the size and shape of your above ground pool:

Round Pool Oval Pool Recommended Pool Pillow Size
12’ and 15’8’ x 12’ and 12’ x 17’4’ x 5’
18’ and 24’12’ x 18’ and 16’ x 32’4’ x 8’
27’ and 33’18’ x 33’ and 21’ x 43’4’ x 15’

Alternatively, you can use larger or multiple pillows. However, it’s important to keep in mind that using too many pillows or pillows that are too oversized generally do not produce the desired results. Pool pillows tend to be most effective when they remain in the center of the pool, which creates the perfect gap as opposed to covering a larger surface area.

So, if you’re wondering how many pool pillows you need, in most cases the answer is either one or two. The following table outlines the maximum pool pillow size and amount based on the size and shape of your pool.

Round PoolOval PoolNot to Exceed
12’ and 15’8’ x 12’ and 12’ x 17’4’ x 8’ (1 pillow)
18’10’ x 19’ and 12’ x 18’(2) 4’ x 5’
21’ and 24’12’ x 24’ and 15’ x 26’(2) 4’ x 8’
27’ and 33’18 x 40’ and 21’ x 43’(2) 4’ x 15’

This table does not list all of the possible size combinations, but it should be a good starting point to find the ideal range for your pool.

How to Use a Pool Pillow

Once you’ve determined the proper size and amount of pool pillows that your pool needs, you must know how to use a pool pillow. Using a pool pillow is simple, as it only involves inflation and installation.

Inflating a Pool Pillow

To inflate your pool pillow, you first want to locate the small red valve on the top of the pillow. By pressing the valve inward with your finger, you’ll see the small opening where the air will go in. For the actual inflation, you can use a number of different tools to get the job done, including a bicycle pump, a hair dryer set to ‘cool,’ or a shop vac on reverse.

Though, you only want to inflate the pillow to between 60 and 80 percent of its total capacity. For the pillow to be effective at absorbing the pressure created by expanding ice, it needs to remain soft. Only filling it up slightly over half of its capacity will allow for appropriate compression. To ensure that the pillow remains inflated during the course of winter, put two strips of duct tape over the air valve.

Installing a Pool Pillow

In order for a pool pillow to work, it has to be positioned in the center of your pool, as this will ensure that it can evenly distribute ice, snow, rainwater, and debris. To make sure the pillow stays in place, you’ll need to use the grommets on the pillow along with some string, rope, or twine. Then, tie the string to the top ledges of your pool, leaving them slightly loose.

If you tie the strings too tightly, the grommets could tear or the string may break and cause the pillow to travel freely throughout the pool.

Pro Tip: Instead of using string, twine, or rope to secure the pool pillow, consider using Velcro. Stick one end of the Velcro to the pillow itself and the other to the underside of your pool, in the exact center.

Pool Pillow Alternatives

There are a number of suggestions regarding pool pillow alternatives on the internet, including inner tubes, yoga balls, and even tire tubes. Although these DIY solutions may work in a pinch, they are not designed to be effective long term. There is also nothing that will do the job as well as an actual pool air pillow will.

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Final Thoughts

Implementing a pool pillow while closing your above-ground pool for the winter is a simple and economical way to prevent damage to your pool caused by cold weather and ice. The size and amount of pool pillows you need will depend on the size and shape of your pool.

Also, keep in mind that larger pools may require more than one pillow for maximum protection. No matter the size, make sure that the pillow remains only partially inflated – around 60% to 80%.

Jessica Stone
Jessica Stone

Jessica considers herself a home improvement and design enthusiast. She grew up surrounded by constant home improvement projects and owes most of what she knows to helping her dad renovate her childhood home. Being a Los Angeles resident, Jessica spends a lot of her time looking for her next DIY project and sharing her love for home design.

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