When we think of pillows, we typically imagine the cushiony supports that we rest our heads on for a good night’s sleep. However, when it comes to pools, the term “pool pillow” refers to something quite different. A pool pillow, also known as an ice compensator or winterizing pillow, serves a specific purpose for outdoor swimming pools located in climates where winter temperatures can lead to freezing. The pool pillow creates a space for ice to expand into, helping to protect the pool walls and cover from damage during the winter months.
Understanding the Need for a Pool Pillow
Outdoor swimming pools in regions with freezing winter temperatures are subjected to the expansion of ice, which can exert significant pressure on the pool walls and the pool cover. Without a buffer, this frozen water can potentially cause cracks or damage the pool structure and tear the cover. This is where a pool pillow comes into play.
The Science Behind Ice Expansion
Water expands when it freezes, and this expansion force can be extremely powerful. It is the same force that can crack boulders over time as water seeps into rock crevices and freezes. In the confined space of a swimming pool, if there’s no give, something has to yield – and it might be the pool walls or the liner.
Protecting the Pool Cover
Pool covers are not designed to bear the weight of expanding ice. Without a pool pillow, ice can solidify as a flat sheet across the pool’s surface. As more water from snowmelt or freezing rain accumulates on top of the cover, the weight can become tremendous. Eventually, it can lead to the cover sinking or tearing, which would mean a costly replacement or repair.
Our Top 5 Pillow Picks
Updated September 2026MFWW Cervical Contour Memory Foam Pillow
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Best hotel-style set. Plush, cooling pillows made to suit side, back and stomach sleepers alike. A safe pick for guest rooms.
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How to Use a Pool Pillow
Using a pool pillow is part of the pool’s winterization process. Here’s a step-by-step guide on how to use a pool pillow correctly:
1. Choosing the Right Size
The size of the pool pillow you need depends on the size of your pool. As a rule of thumb, it should be large enough to absorb and compensate for the pressure from the ice without being so big that it’s difficult to manage.
2. Inflating the Pillow
The pillow should be inflated to about half or three-quarters full. This allows some give and makes it less likely that the pillow itself will pop under the pressure of ice or snow. It’s similar to inflating a beach ball; you want it to be firm yet still a bit flexible.
3. Positioning the Pillow
The pillow is typically placed in the center of the pool. It’s held in place by ropes or strings that are anchored around the pool’s edges. This ensures that the pressure from the ice will be evenly distributed, reducing the stress on any one point in the pool walls or cover.
4. Securing the Pool Cover
Once the pool pillow is in position, you then place the pool cover over it. The cover should be secured tightly around the edges of the pool to prevent it from blowing away or allowing debris to enter the pool during the off-season.
Maintenance and Considerations
It’s important to remember that a pool pillow is not a ‘set it and forget it’ item. Throughout the winter, it requires some maintenance and attention.
Monitoring Air Pressure
Changes in temperature can cause the air inside the pillow to expand or contract, potentially leading to under-inflation or over-inflation. Therefore, it’s wise to periodically check the pillow, especially following significant temperature fluctuations.
Dealing With Snow Accumulation
After heavy snowfall, it’s crucial to remove the snow from the pool cover. The weight of snow can greatly increase the pressure on the pool pillow and pool cover, risking damage to both. Use a broom or a pool cover pump to clear the snow off.
Addressing Leaks and Tears
Inspect the pillow for any signs of leaks or tears, which can occur due to weather conditions or animals. A punctured pool pillow will not perform its duty, so it should be patched or replaced if damage is noticed.
Pool Pillow Alternatives
While pool pillows are effective, some pool owners opt for alternatives. These can include foam rope, air-filled toys, or even professional products designed to provide the same level of protection without the hassle of inflating and securing a pillow.
The Bigger Picture: Comprehensive Winterizing
It’s important to realize that a pool pillow is just one component of the larger winterizing process. Other steps to take include properly balancing the pool’s water chemistry, lowering the water level to an appropriate depth, and draining all the water from the pool’s pipes and filtration system to prevent any freezing and cracking.
Expert Advice
Before you initiate the winterizing process, it’s a good idea to consult with a pool professional, especially if this is your first time winterizing a pool. They can provide you with tips and best practices specific to your pool’s type, size, and material, as well as the particular climate conditions in your area.
Finishing Thoughts
A pool pillow is an essential component for those in colder regions intent on protecting their backyard oasis from the rigors of winter. It acts as a buffer against the pressure of expanding ice, helping to preserve the integrity of the pool walls and cover. Regular maintenance of the pool pillow and a thorough understanding of the winterization process will go a long way in ensuring that your pool remains in good condition throughout the winter, ready for another season of enjoyment when warmer temperatures return. Remember, winterizing your pool is an investment in its longevity and in countless future days of relaxation and fun.
