9 Essential Items for Winterizing Your Backyard Pool

Watching the autumn leaves drift onto a glassy pool surface is a beautiful sight, but it also signals that it is time to close up shop before the first hard freeze hits. Skipping or rushing through your pool winterization process is a gamble that almost always ends in split pipes, stained plaster, and a massive repair bill come spring. Investing in the right seasonal gear now ensures that your backyard oasis remains protected through the coldest months and opens up crystal clear next season.

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Why Proper Winterization Prevents Costly Spring Repairs

Freezing water is a powerful force of nature, expanding by roughly nine percent as it solidifies. In a backyard pool, this expansion exerts immense pressure on underground PVC plumbing, pump housings, and delicate skimmer walls. Without proper protection, this pressure can easily crack thick plastics and rupture pipes, leading to underground leaks that cost thousands of dollars to locate and excavate in the spring.

Chemical preparation is just as critical as mechanical protection during the off-season. Leaving pool water untreated invites microscopic algae spores to thrive under the cover during mild late-autumn and early-spring days. This turns a pristine swimming environment into a dark, staining soup that ruins plaster finishes and requires weeks of costly chemical shock treatments to resolve.

Taking a systematic approach to winterization saves time, money, and frustration. Utilizing specialized winterizing accessories ensures that water is kept out of vulnerable spaces and that the remaining liquid stays chemically stable. A small investment in quality winter gear now translates to a seamless, headache-free pool opening when the warm weather returns.

Pool Cover – Loop-Loc Safety Pool Cover

A reliable pool cover is your primary defense against winter weather, falling debris, and backyard safety hazards. It prevents heavy snow loads from directly entering the pool while blocking the sunlight that algae needs to multiply. Beyond water cleanliness, a high-quality cover acts as a structural safety barrier that protects pets, wildlife, and family members from accidental falls into cold water.

The Loop-Loc Safety Pool Cover is the industry standard for securing an inground pool for the winter. Known for its incredible strength, this cover uses ultra-tough, double-webbed mesh that allows rainwater to drain through while blocking fine debris and blocking out weed-promoting sunlight. The heavy-duty brass anchors and stainless steel tension springs keep the cover drum-tight across the deck, ensuring it can handle immense weight without sagging.

When purchasing, precise measurements are critical because these covers are custom-sized to match the exact footprint of your pool, including steps and water features. The initial installation requires drilling anchor holes into your concrete or wood decking, which calls for a hammer drill and a steady hand. Once these anchors are set, however, putting the cover on and taking it off each season becomes a straightforward, one-person job.

• Material: High-density, UV-stabilized polypropylene mesh
• Weight Capacity: Engineered to support heavy snow loads and accidental weight
• Hardware: Corrosion-resistant brass anchors and stainless steel springs

This cover is ideal for inground pool owners who want a permanent, high-safety solution that lasts for decades. It is not suitable for above-ground pools or temporary setups that lack a solid deck for anchoring.

Winterizing Kit – In The Swim Deluxe Closing Kit

As pool water sits stagnant for several months, chemical levels naturally degrade, leaving the pool vulnerable to organic staining and aggressive algae blooms. A specialized winterizing chemical kit delivers a concentrated dose of slow-release sanitizers and protectants designed to work in cold temperatures. This ensures the water stays clear and the pool walls remain free of scale and metallic stains until spring.

The In The Swim Deluxe Closing Kit simplifies this chemical prep by providing pre-measured doses of high-strength winterizing agents. It includes non-chlorine winter shock to oxidize contaminants, a highly concentrated copper-free algaecide, and a powerful stain-and-scale preventer. The standout feature is the slow-releasing winter chemical floater, which continuously dispenses sanitizer long after the initial shock treatment dissipates.

Before adding this kit, the pool water must be thoroughly balanced, and the water level should be lowered to your winterization target. You will need to run the pool filter for several hours after adding these chemicals to ensure they are fully circulated through the entire pool before shutting down the pump.

• Coverage Capacity: Sized for pools up to 35,000 gallons
• Included Items: Chlorine-free winter shock, winter algaecide, metal rust inhibitor, and slow-release chemical dispenser
• Formula: Non-staining, compatible with all pool surface types

This kit is perfect for owners of large inground or above-ground pools who want a reliable, all-in-one chemical solution to avoid guesswork. It is less suitable for small, temporary pools that can be easily drained and refilled each year.

Pool Air Pillow – Robelle Ice Equalizer Pillow

When water freezes in an above-ground pool, it expands outward, pushing directly against the delicate steel walls and pool liner. An air pillow sits in the center of the pool underneath the cover to absorb this inward pressure. As the ice layer expands toward the middle, it compresses the soft air pillow rather than warping or rupturing the pool walls.

The Robelle Ice Equalizer Pillow is built from heavy-duty 16-gauge vinyl, making it exceptionally resilient against freezing temperatures and constant compression. It features a secure, leak-resistant valve that prevents air from escaping over months of cold weather. The reinforced corner grommets allow you to easily tie ropes to the pillow, keeping it perfectly centered in the pool.

A common mistake is fully inflating the pillow, which makes it prone to popping under the weight of winter snow. Only inflate the pillow to about 60 to 70 percent of its capacity to allow plenty of room for compression. Additionally, you must secure it tightly with nylon strings to prevent it from drifting to the sides of the pool during winter winds.

• Material: 16-gauge heavy-duty vinyl
• Inflation Recommendation: Inflate to 60–70% for optimal expansion room
• Attachment: Heavy-duty brass or plastic grommets on all four corners

This pillow is a must-have for above-ground pool owners in cold-climate regions where thick ice sheets form on the pool surface. It is unnecessary for inground pools using standard tension safety covers.

Expansion Plug – Swimline Rubber Expansion Plug

Once water is cleared from the pool plumbing lines, you must seal the openings to prevent water from creeping back in and freezing. Expansion plugs slip into the return jets and cleaner lines, expanding to create an airtight and watertight barrier inside the pipe. This simple mechanical seal is the only thing preventing freezing water from re-entering your underground pipes.

The Swimline Rubber Expansion Plug features heavy-duty, tapered rubber walls that deform smoothly under compression to fill any small gaps or imperfections inside the pipe. The non-corrosive nylon wing nuts make it easy to tighten the plug by hand without needing specialized tools. The stainless steel bolts resist rust, ensuring the plugs can be easily removed when spring arrives.

Sizing is critical here, as pool plumbing lines typically use either 1.5-inch or 2-inch fittings. It is vital to measure your return jets before purchasing to ensure a tight, flush fit. Avoid over-tightening the wing nuts, as excessive force can crack older, brittle plastic fittings inside the pool wall.

• Material: High-grade rubber with a rust-resistant stainless steel bolt
• Sizes: Available in standard pool sizes, including #10 (1.5-inch) and #11 (1.75-inch)
• Hardware: Large nylon wing nut for tool-free tightening

These plugs are essential for any inground pool owner in freezing climates who needs to seal off return lines and wall fittings. They are not necessary for pools that are completely drained or located in freeze-free southern climates.

Pool Antifreeze – Splash Pool and Spa Antifreeze

Even after blowing out pool plumbing lines, small pockets of water can pool in low-lying elbows and underground pipe bends. If this residual water freezes, it can easily split PVC pipes and ruin your filtration system. Pouring specialized pool antifreeze down the lines acts as a critical safety margin, preventing any remaining water from freezing and causing structural damage.

Splash Pool and Spa Antifreeze is formulated with high-quality propylene glycol, which provides reliable freeze protection down to -50°F. Unlike automotive antifreeze, this formula is non-toxic, eco-friendly, and completely safe for pool liners, fiberglass, and plaster surfaces. If a small amount leaks into the pool water during spring startup, it will not harm swimmers or disrupt pool chemistry.

This product must never be added directly to the main pool water, as it is only designed for concentrated use inside closed plumbing lines. It is also important to note that you should never use automotive ethylene glycol antifreeze in your pool system, as it is highly toxic to pets and humans.

• Active Ingredient: Non-toxic propylene glycol
• Temperature Rating: Safe down to -50°F (-46°C)
• Compatibility: Safe for PVC, copper, and plastic plumbing systems

This product is highly recommended for inground pool owners living in deep-freeze regions where underground pipes sit above the frost line. It is not necessary for pool owners in mild climates who do not experience sustained freezing temperatures.

Pool Cover Pump – Wayne WAPC250 Water Removal Pump

Solid pool covers naturally collect rainwater, melting ice, and heavy snow throughout the winter. This accumulated weight places immense tension on the cover straps, anchors, and pool walls, risking a catastrophic structural failure. A specialized pool cover pump automatically removes this water, keeping the cover light and preventing dirty puddle water from slipping into the clean pool below.

The Wayne WAPC250 Water Removal Pump is a highly efficient submersible pump designed specifically for this taxing outdoor task. It features smart-sensing technology that automatically turns the pump on when water levels reach 2.1 inches and shuts it off when the surface is clear. With a flow rate of up to 3,000 gallons per hour, it quickly clears large accumulations of water before they can freeze.

Because the pump will be left outdoors in freezing temperatures, it features an integrated freeze-protection mechanism to prevent motor damage. The base of the pump has a built-in strainer that filters out leaves and twigs, but you must still periodically check the pump to clear away heavy leaf blockages.

• Flow Rate: Up to 3,000 gallons per hour at 0 feet of head
• Activation: Smart automatic sensor with freeze protection
• Power Cord: 25-foot heavy-duty power cord with GFCI compatibility

This pump is a crucial tool for anyone using a solid safety cover, standard tarp, or above-ground winter cover. It is not needed for pool owners who utilize mesh safety covers, which allow rainwater to drain directly into the pool.

Skimmer Guard – Gizzmo Ultra Freeze Protection

The pool skimmer is one of the most vulnerable parts of a pool during the winter because it sits right at the water line where ice forms first. When water inside the skimmer throat freezes, it expands outward, easily cracking the delicate plastic housing and causing a major underground leak. A skimmer guard acts as an expansion absorber, collapsing under pressure to protect the skimmer walls from cracking.

The Gizzmo Ultra Freeze Protection is a rugged, hollow plastic tube that screws directly into the bottom of your skimmer. When ice forms inside the skimmer, the Gizzmo collapses inward, absorbing the crushing force of the expanding ice. This model also serves as an airtight plug, sealing off the plumbing line below to prevent water from entering the pipe.

Before screwing the Gizzmo into place, wrap the threads with several layers of Teflon tape to ensure a watertight seal. This prevents water from slowly leaking down into your blown-out plumbing lines over the winter. Always ensure you purchase the correct size, as the Ultra version features extended length for deeper skimmer wells.

• Design: Heavy-duty, crushable plastic tube
• Size Options: Fits standard 1.5-inch or 2-inch internal skimmer threads
• Length: 16 inches for maximum deep-skimmer protection

This is an indispensable tool for inground pool owners who live in areas that experience deep winter freezes. It is not necessary for above-ground pools that use a simple winter cover plate or are fully drained below the skimmer level.

Pool Leaf Net – Blue Wave Leaf Net Cover

Falling leaves are a major headache during autumn pool closings, quickly piling up on top of your main winter cover. Once wet, these leaves rot into a heavy, acidic sludge that is incredibly difficult to remove in the spring. A leaf net cover is a lightweight mesh screen that catches these leaves, allowing you to peel them off the pool in one quick motion.

The Blue Wave Leaf Net Cover is constructed from a durable, woven polyethylene mesh that resists tears from twigs and heavy wind. It features a generous three-foot overlap, ensuring that leaves cannot blow underneath the edges and onto the main cover. Once all the local trees have finished shedding their leaves, you simply lift the net off, leaving a clean pool cover beneath.

The key to using this net successfully is removing it before the first major winter freeze or heavy snowfall. If you wait too long, the wet leaves will freeze solid to your winter cover, making it impossible to lift the net without tearing it.

• Material: Woven polyethylene mesh with UV inhibitors
• Overlap: 3-foot extra material for secure coverage
• Attachment: Heavy-duty grommets with winch and cable (for above-ground pools)

This net is a fantastic time-saver for pool owners who have deciduous trees near their yard. It is not necessary for those who live in open areas with minimal tree cover.

Pool Water Bags – Robelle Double Chamber Bags

Solid winter covers on inground pools need to be secured around the perimeter to prevent heavy winds from lifting them. Traditional weights like concrete blocks or bricks can damage the pool coping and tear the delicate vinyl cover if they slide. Vinyl water bags provide a soft, heavy ballast that holds the cover firmly in place without risking damage to your pool.

The Robelle Double Chamber Bags utilize a dual-tube design that prevents the bags from rolling off the pool deck when filled. Made from heavy-duty, 18-gauge vinyl, they are highly resistant to UV rays and punctures from ice or twigs. The leak-resistant valves are easy to open and close, making filling and draining a simple task.

When filling these water bags, never fill them more than 50 to 70 percent of their capacity. Leaving empty space inside the bag allows the water to expand into ice without splitting the heavy-duty vinyl seams. Additionally, placing the bags end-to-end around the entire perimeter ensures that wind cannot catch the edges of the cover.

• Material: 18-gauge heavy-duty vinyl
• Design: Double chamber to prevent rolling on sloped decks
• Length: Available in standard 8-foot and 10-foot lengths

These bags are essential for inground pool owners who use traditional solid water-bag covers to winterize their pools. They are not required for pools equipped with anchored safety covers.

How to Safely Blow Out Your Pool Plumbing Lines

Blowing out your pool plumbing lines is the most critical step in preventing freeze damage to your underground pipes. This process involves using high-volume air to push all standing water out of the lines, creating an empty space where ice cannot form. Without a complete blowout, water will settle in low spots, freeze, and expand, leading to ruptured PVC pipes beneath your concrete deck.

To begin, lower the pool water level to roughly four to six inches below the skimmer and return jets. Connect a high-volume pool line blower or a heavy-duty shop vacuum to the skimmer suction line or the pool pump basket. Turn on the blower and watch for air to force water out of the return lines inside the pool, which will manifest as a loud bubbling and spraying action.

While the air is still actively blowing and bubbling, quickly insert a rubber expansion plug into each return jet and tighten the wing nut to seal it. For the main drain, blow air until a massive geyser of bubbles erupts from the bottom of the pool, then quickly close the valve at the equipment pad to create an airtight “air lock.” Finally, pour a gallon of pool antifreeze down the skimmer line for an added layer of safety before sealing it with a Gizzmo.

Monitoring Your Covered Pool Throughout the Winter

Winterizing your pool is not a “set-it-and-forget-it” chore that ends when the cover is secured. Routine monitoring throughout the winter months is essential to catch minor issues before they escalate into major, expensive repairs. A quick bi-weekly inspection of your pool area ensures that your protective gear is performing exactly as intended.

Pay close attention to water accumulation on solid covers, as heavy puddles can stress the anchors or drag the cover down. Run your cover pump after rainstorms or thawing events to keep the cover as dry and lightweight as possible. For above-ground pools, check that the air pillow remains inflated and centered, adjusting the tie lines if wind has shifted it to one side.

It is also wise to peel back a corner of the cover in late winter or early spring to check the chemical state of the water. If you experience an unseasonably warm spell, the water temperature may rise enough to activate dormant algae spores. Adding a quick dose of winter algaecide at this stage will prevent a green pool opening when spring officially arrives.

Conclusion

Using the right tools and taking a methodical approach to pool winterization is the best way to safeguard your backyard investment. By securing high-quality covers, heavy-duty plugs, and reliable pumps, you ensure that freezing temperatures will not cause costly damage to your plumbing. A little seasonal effort now guarantees a stress-free spring reopening, allowing you to dive back into clean, clear water when summer returns.