10 Essential Supplies for Closing a Backyard Pool for Winter

Watching the leaves change color is a beautiful transition, but for pool owners, it signals the urgent need to protect a major backyard investment. Shutting down an in-ground or above-ground pool for the freezing months requires more than just throwing a tarp over the water and hoping for the best. Equipping yourself with the right seasonal supplies now prevents catastrophic pipe freezes, algae blooms, and structural damage before the first hard frost hits.

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Why Winterizing Your Pool Correctly Saves Money

Skipping or rushing the pool closing process is one of the most expensive mistakes a homeowner can make. When water freezes, it expands by about nine percent, exerting immense pressure on PVC pipes, skimmer wells, and concrete shells. A single cracked underground pipe can cost thousands of dollars to locate and excavate, transforming a minor autumn chore into a major construction project come spring.

Proper winterization also preserves water quality, meaning startup in the spring requires fewer chemicals and less filtration time. Leaving a pool open to the elements or improperly balanced creates a breeding ground for stubborn black algae and deep organic staining. Instead of spending your first warm weekend scrubbing plaster and buying expensive shock treatments, a protected pool opens crystal clear and ready for swimming.

Investing in high-quality winterizing gear pays for itself after just one season of avoiding emergency repairs. From heavy-duty covers that keep out safety hazards to specialized plugs that isolate plumbing lines, each tool serves as cheap insurance against the brutal forces of winter.

Pool Safety Cover – Loop-Loc Safety Pool Cover

An open pool during winter is a severe safety hazard for children, pets, and local wildlife, while also acting as a giant collector for debris. Unlike standard floating tarps that sink under the weight of snow, a tensioned safety cover anchors directly into the pool deck to create an impenetrable barrier. This setup keeps leaves out of the water and prevents accidental submersion.

The Loop-Loc Safety Pool Cover is the industry benchmark because of its legendary “mesh that lets water through but blocks debris” design. Built with ultra-strong polypropylene mesh and secured with heavy-duty brass anchors and stainless steel springs, it can easily support the weight of an adult. This eliminates the dangerous puddle of standing water that typically accumulates on solid covers, reducing drowning risks and breeding grounds for mosquitoes.

• Material: Super Dense Mesh (blocks light, lets water drain)
• Break Strength: Exceeds ASTM safety standards
• Anchoring: Flush-mount brass anchors for concrete, pavers, or wood decks
• Included Hardware: Installation tool, tamping tool, brass anchors, and stainless steel springs

Before buying, precise measurements of the pool’s coping-to-coping dimensions and any unique features like water fountains or steps are mandatory. This cover requires drilling anchors into the surrounding deck, meaning it is best suited for pool owners looking for a permanent, multi-season safety solution rather than a quick, cheap fix. It is not ideal for those with limited deck space or above-ground pools without decking.

Winter Chemical Kit – In The Swim Deluxe Kit

Algae does not stop growing just because the temperature drops; it simply slows down until the early spring sun warms the water under the cover. A dedicated winter chemical kit slow-releases sanitizers and enzymes over the long off-season to keep water clear and prevent staining. Without these specialized, cold-tolerant formulas, you will uncover a dark green swamp in May.

The In The Swim Deluxe Kit provides a comprehensive, pre-measured chemical regimen designed specifically to survive freezing temperatures. It features a combination of powerful winter shock, a long-lasting algaecide, a metal chelating agent to prevent rust staining, and a unique slow-release chemical floater. The star of the kit is the non-chlorine winterizer dispenser, which slowly sanitizes the water without bleaching the pool liner.

• Pool Size Capacity: Kits available for pools up to 10,000, 22,000, and 35,000 gallons
• Kit Components: Winterizer canister, winter shock, winter algaecide, and stain preventer
• Compatibility: Safe for all pool types, including vinyl, fiberglass, and plaster

Ensure the pool water is fully balanced (pH, alkalinity, and calcium hardness) before adding this kit, as these chemicals work best in balanced water. This kit is perfect for owners who want a straightforward, all-in-one chemical solution without the guesswork of buying separate bottles. It is less ideal for pools using salt chlorine generators that require specific cold-weather mineral stabilizers not included here.

Pool Air Pillow – Robelle Ice Equalizer Pillow

When water freezes in an above-ground pool, it expands outward, putting tremendous lateral pressure on the pool walls and the cover. An air pillow sits in the center of the pool under the cover, acting as a compression cushion that absorbs this expansion force. As the ice sheet grows, it collapses the pillow rather than pushing outward against your expensive steel walls or tearing the cover seams.

The Robelle Ice Equalizer Pillow utilizes ultra-thick, puncture-resistant vinyl that stands up to sub-zero temperatures without cracking. Unlike cheap single-valve pillows that deflate after the first hard freeze, this model features a secure leak-proof valve and reinforced grommets on the corners. These grommets allow you to anchor the pillow securely in the exact center of the pool using durable nylon cords.

• Material: Heavy-duty 16-gauge vinyl
• Size Options: 4′ x 4′, 4′ x 8′, and 4′ x 15′ sizes
• Inflation Valve: Dual-secure valve to prevent air loss
• Attachment Points: Reinforced corner grommets

Do not inflate the pillow to 100 percent capacity; filling it to about 70 to 80 percent leaves room for compression when ice presses against it. This product is absolutely essential for above-ground pool owners and those using solid vinyl covers on in-ground pools. It is not necessary for those using tightly tensioned mesh safety covers that do not sit directly on the water’s surface.

Pool Cover Pump – Wayne WAPC250 Removal Pump

Accumulated rain and melted snow on a solid pool cover create a heavy, stagnant pool of water that strains the cover seams and anchors. This standing water also attracts mosquitoes and makes cover removal in the spring nearly impossible without dumping dirty debris back into the clean pool. An automatic cover pump prevents this headache by continuously evacuating water as soon as it accumulates.

The Wayne WAPC250 Removal Pump stands out because of its smart, oil-free automatic sensing technology that turns the pump on when water reaches 2.1 inches and off when it drops below 0.75 inches. Its generous, wide-base design prevents the pump from tipping over on uneven cover surfaces, while the built-in debris strainer keeps leaves from clogging the impeller. Operating at up to 3,000 gallons per hour, it clears heavy downpours in a fraction of the time of manual pumps.

• Flow Rate: Up to 3,000 Gallons Per Hour (GPH)
• Power Source: 120-volt plug with a 25-foot power cord
• Discharge Connection: Standard 3/4-inch garden hose thread
• Sensor Type: Reed switch automatic sensing

Keep in mind that the pump must remain plugged in to function automatically, requiring a safe, outdoor-rated GFCI outlet nearby. It is an indispensable tool for anyone utilizing a solid winter cover or tarp. However, owners of free-draining mesh safety covers do not need this pump, as water naturally filters through the mesh into the pool below.

Winter Expansion Plug – Hayward SP1022C Plug

Once you blow the water out of your pool’s plumbing lines, you must seal those lines hermetically to prevent water from seeping back in and freezing. Standard plastic directional eyeballs will not cut it; you need rubber expansion plugs that expand inside the pipe to create a watertight barrier. These simple plugs are the only line of defense protecting your underground PVC pipes from cracking under ice expansion.

The Hayward SP1022C Plug is the gold standard for pool technicians due to its high-grade neoprene construction and heavy-duty nylon wing nuts. Unlike cheap rubber plugs that degrade when exposed to chlorine and winter chemicals, the Hayward neoprene resists chemical breakdown and remains pliable in freezing conditions. The large wing nut design allows for quick, hand-tightened installation without stripping the threads or requiring specialized tools.

• Material: Non-corrosive neoprene rubber with a stainless steel bolt
• Size: Standard 1.5-inch thread size (fits most return lines)
• Hardware: Heavy-duty nylon wing nut
• Fit Type: Expandable compression seal

Before ordering, verify the inner diameter of your return lines, as older pools or specialized spa jets may require 1.25-inch or 2-inch plugs instead of the standard 1.5-inch. This plug is crucial for any pool owner with an in-ground system or hard-plumbed above-ground pool in freeze-prone regions. It is not required if you live in a climate where temperatures never drop below freezing.

Skimmer Guard – Ultra Gizzmo Skimmer Protector

The pool skimmer is one of the most vulnerable parts of your pool because it sits right at the freeze line and holds standing water. If water freezes inside the rigid plastic skimmer well, the expansion will easily crack the throat, requiring a costly excavation and replacement. A specialized skimmer guard absorbs this destructive expansion force while simultaneously sealing the plumbing line below.

The Ultra Gizzmo Skimmer Protector is a heavy-duty, hollow plastic tube designed to collapse inward when ice forms inside the skimmer. Featuring built-in 1.5-inch and 2-inch threads at the bottom, it screws directly into the skimmer’s plumbing line to act as a plug and expansion absorber all at once. The “Ultra” designation means it features a blow-molded, high-density construction that can be reused season after season without failing.

• Thread Sizes: Dual 1.5-inch and 2-inch tapered threads
• Material: High-density polyethylene
• Length: 16 inches (designed for deep skimmer wells)
• Style: Hollow, crushable design to absorb ice expansion

Ensure you wrap the threads of the Gizzmo with Teflon tape before screwing it in to guarantee a completely watertight seal. This tool is a non-negotiable lifesaver for in-ground pools with standard built-in skimmers in snowy climates. It is not compatible with small, clip-on surface skimmers typically found on temporary, soft-sided above-ground pools.

Pool Antifreeze – Splash Fast Acting Antifreeze

Even after blowing out pool plumbing lines, small pockets of water can pool in low spots or sagging underground pipes. If this residual water freezes, it can easily split PVC pipes and cause slow, hard-to-find leaks. Adding pool-specific non-toxic antifreeze to the plumbing lines ensures that any remaining moisture cannot freeze and expand.

Splash Fast Acting Antifreeze is formulated specifically for pool filtration systems and is completely safe for both pool liners and plumbing gaskets. Unlike automotive antifreeze, which contains highly toxic ethylene glycol, this formula uses non-toxic propylene glycol that will not harm swimmers or pets when the pool is reopened in the spring. It provides reliable burst protection down to temperatures as low as -50 degrees Fahrenheit.

• Chemical Base: Non-toxic propylene glycol
• Freeze Protection: Burst protection down to -50°F (-46°C)
• Volume: 1-gallon bottles
• Compatibility: Safe for copper, PVC, and flexible plastic piping

Never pour automotive antifreeze into your pool system, as it is highly toxic and extremely difficult to safely filter out in the spring. This product is designed specifically for lines that cannot be 100 percent cleared of water due to plumbing layout or low-powered blowers. It is not necessary for pool owners in southern climates that experience only brief, mild frosts.

Pool Leaf Net – Blue Wave Bronze Leaf Net Cover**

Deciduous trees shed their leaves right around the time you close your pool, turning solid winter covers into wet, decaying bogs. Removing thousands of wet leaves in the spring is a backbreaking task that often results in decaying organic material slipping past the cover into your water. A lightweight leaf net sits on top of your main cover during autumn to collect leaves, allowing you to peel them off in one swift motion once the trees are bare.

The Blue Wave Bronze Leaf Net Cover is constructed from exceptionally durable, woven polyethylene mesh that withstands the tugging of heavy, wet foliage. It features a generous four-foot overlap that prevents the net from slipping off the pool edges under the weight of accumulated leaves. The mesh openings are sized perfectly to catch small leaves and twigs while allowing water to pass through freely, keeping the net lightweight and easy to handle.

• Material: Heavy-duty woven polyethylene mesh
• Overlap: 4-foot overlap to ensure secure fit
• Included Hardware: Heavy-duty winch and vinyl-coated steel cable for above-ground models
• Color: Forest Green/Black (blends with winter landscapes)

The key to using this net successfully is removing it before the first major snowstorm of the year. If left on during heavy snow, the weight will lock the net and the leaves down onto the main cover, rendering it impossible to remove. This net is an invaluable time-saver for pool owners surrounded by heavy foliage, but unnecessary for those in arid or pine-only environments.

Pool Water Bag – Robelle Double Chamber Tube

If you use a traditional solid tarp cover on an in-ground pool, you need a heavy, reliable method to weigh down the perimeter. Bricks, concrete blocks, and timber will quickly wear holes through vinyl covers and can easily slide into the pool, damaging the liner. Heavy-duty water bags provide a soft, heavy, and non-damaging ballast that contours perfectly to the pool coping.

The Robelle Double Chamber Tube features a two-channel design that prevents the bag from rolling out of position on sloped or uneven pool decks. Constructed from thick, puncture-resistant 18-gauge vinyl, these bags resist cracking in freezing temperatures and contain UV inhibitors to prevent sun degradation. The dual-chamber design also offers built-in redundancy: if one chamber gets punctured, the other remains filled to keep the cover secure.

• Material: Heavy-duty 18-gauge vinyl
• Design: Double-chamber layout to prevent rolling
• Length Options: Available in 8-foot and 10-foot lengths
• Valve Style: Leak-resistant freeze-expansion valves

Do not fill water bags to the brim; leaving about one-third of the bag empty allows room for water expansion as it freezes into solid ice. These bags are the safest and most effective option for securing traditional solid vinyl covers on in-ground pools. They are completely unnecessary for pools equipped with anchored tension safety covers.

Pool Cover Seal – Wintercare Cover Seal Wrap

Wind is the ultimate enemy of above-ground pool covers, slipping underneath the edges and ballooning the cover like a sail. This constant flapping can tear cover seams, pull out securing cables, and dump cold, dirty air and leaves directly into the clean pool water. A specialized cover seal wrap acts like heavy-duty plastic wrap, securing the cover flush against the pool wall to lock out the wind.

Wintercare Cover Seal Wrap is a highly elastic, UV-stabilized stretch film designed specifically to survive harsh winter weather without tearing or losing its grip. It clings tightly to itself and the pool wall, creating a smooth, airtight seal that prevents wind from getting under the cover lip. By wrapping the perimeter several times, you also prevent insects and leaves from crawling under the cover over the winter.

• Material: High-yield, UV-stabilized stretch polymer
• Width: 80-gauge thickness, typically 500 feet per roll
• Application: Clings directly to itself without leaving sticky adhesive residue
• Durability: Formulated for cold-weather elasticity and tear resistance

This wrap must be applied tightly around the top rail of the pool, which requires walking the perimeter of the pool several times. It is designed specifically for above-ground pool configurations where the cover hangs over the outside walls. It is not suitable or effective for in-ground pools with flat, deck-flush safety covers.

How to Properly Blow Out Pool Lines for Winter

Blowing out the plumbing lines is the most critical step in preventing freeze damage to your pool’s circulation system. Start by lowering the water level in the pool below the skimmer mouth, then hook up a high-volume blower or heavy-duty shop vac to your pump’s filter system. Turn on the blower and open each line one by one—starting with the return jets furthest from the equipment pad—to force all standing water back into the pool.

Once you see a violent geyser of air and mist blowing out of a return jet, quickly push a winter expansion plug into the opening to seal it while the air is still flowing. Repeat this process for every return line and the skimmer, ensuring that no water is left standing inside the lines. Finally, blow out the main drain line at the bottom of the pool until you see a steady stream of air bubbles, then quickly close the valve at the filter pad to create an airtight lock.

A common mistake is using an air compressor with high pressure but low volume (CFM), which cannot push enough water out of large-diameter pool pipes. Always use a high-volume blower designed specifically for pools to ensure a complete blowout. Once all lines are plugged and secured, pour a small amount of non-toxic pool antifreeze into the skimmer throat as a final backup measure.

Conclusion

Closing a backyard pool properly requires a bit of time and the correct arsenal of tools, but the payoff is immense. By investing in heavy-duty safety covers, reliable expansion plugs, and protective chemicals, you shield your pool from costly structural and plumbing damage. When spring rolls around, you will be rewarded with a clean, clear pool that is ready for another season of fun.