Pool Closing Supplies: 9 Essentials for Winter

As autumn leaves begin to fall and the evening air turns crisp, backyard pool owners must shift their focus from daily swimming to seasonal preservation. Neglecting the winterization process can turn a pristine oasis into a costly nightmare of cracked pipes and torn liners once sub-zero temperatures arrive. Preparing your pool for the freeze requires the right strategy and a specific set of tools designed to withstand the brutal winter elements.

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Why Proper Winterization Saves Your Pool From Ice Damage

When temperatures drop below freezing, water undergoes a powerful physical transformation, expanding by nearly nine percent as it turns to ice. In an unsecured backyard pool, this expansion exerts thousands of pounds of pressure against vinyl liners, concrete walls, and underground plumbing. Without proper winterization, this outward force will crack pipes, split skimmers, and cause structural damage that is incredibly expensive to repair.

Beyond structural protection, closing a pool correctly keeps the water chemistry balanced and blocks organic debris from decaying over the off-season. A neglected pool becomes a breeding ground for algae and staining minerals, turning spring opening into a grueling, multi-week cleanup. Investing in the right gear now ensures that your pool remains a static, protected vessel until the warm weather returns.

Pool Cover – Loop-Loc Mesh Safety Pool Cover

A high-quality pool cover acts as the primary shield against winter elements, preventing heavy snow, windblown debris, and animals from entering the pool. Standard tarp covers often collect dangerous puddles of melting snow, creating a drowning hazard and straining the pool walls. A tension-secure safety cover keeps the barrier taut, clean, and safe throughout the harshest winter storms.

The Loop-Loc Mesh Safety Pool Cover is a premier choice for this task because its patented weave lets water drain through while blocking ultra-fine debris. Its high-tensile brass anchors and stainless steel springs secure the cover directly into the pool deck, allowing it to support thousands of pounds of snow load without sagging. This mesh design also eliminates the need for a cover pump during heavy rainstorms, as the water naturally filters into the pool below.

• Material: Lightweight, high-strength polypropylene mesh
• Safety Rating: Exceeds ASTM safety standards for weight load
• Inclusions: Heavy-duty brass anchors, installation tool, and storage bag

Buyers should note that while mesh covers let water pass through, they also allow fine silt and sunlight to enter, which can encourage early spring algae growth if the pool is closed too warm. Precision measuring of your pool’s coping and step layout is absolutely critical before ordering to ensure a drum-tight fit. This cover is ideal for homeowners seeking a permanent, ultra-safe winter barrier, but it is not suitable for those without concrete or wood decking to anchor the tension springs.

Winter Chemical Kit – In The Swim Deluxe Winterizing Kit

Closing a pool with balanced water is only half the battle; those chemicals naturally dissipate over months of dormancy, leaving the water vulnerable to aggressive algae blooms. A specialized winter chemical kit slow-releases sanitizers and algaecides to maintain water clarity as temperatures fluctuate. This prevents staining on the pool walls and simplifies the spring opening process immensely.

The In The Swim Deluxe Winterizing Kit provides a pre-measured, highly potent combination of winterizing powder, non-chlorine shock, metal rust preventer, and a slow-dissolving winter floater. The included time-release chemical dispenser ensures that sanitizer is continuously distributed through the water even when the pump is turned off. This chemical blend is formulated to remain active in cold water without damaging vinyl liners or plaster finishes.

• Capacity Options: Sized for pools up to 10,000, 20,000, or 35,000 gallons
• Key Ingredients: Copper-free algaecide, non-chlorine oxidizer, stain inhibitor
• Lifespan: Active protection for up to six months of winter storage

For the best results, pool owners must run the pool filter for at least four hours after adding these chemicals to ensure thorough mixing before lowering the water level. This kit is perfect for owners of both inground and above-ground pools who want a foolproof, all-in-one chemical regimen. It is not recommended for pools that are closed late in the season when water temperatures are already below 50 degrees Fahrenheit, as the active ingredients require slightly warmer water initially to distribute effectively.

Pool Air Pillow – Robelle Ice Equalizer Pillow

In an above-ground pool, freezing water expands outward, applying immense pressure directly to the pool’s metal walls and vinyl liner. An air pillow sits in the center of the pool under the winter cover, acting as an expansion cushion that absorbs the inward squeeze of the freezing ice sheet. Instead of ice pushing outward against the pool walls, it collapses the pillow inward, saving the structure from catastrophic buckling.

The Robelle Ice Equalizer Pillow is engineered to withstand extreme sub-zero compression due to its heavy-duty 16-gauge vinyl construction. It features a reliable dual-valve system that prevents air leakage, along with reinforced corner grommets to keep the pillow securely centered. Its rugged build ensures it won’t pop when the ice sheet begins to shift and compress during mid-winter thaws.

• Dimensions: Available in 4’x4′, 4’x8′, and 4’x15′ sizes
• Material: Commercial-grade, cold-crack resistant vinyl
• Inflation Type: Quick-fill valve compatible with air pumps

A common mistake is fully inflating the pillow; it should only be filled to about 60% to 70% of its capacity to allow room for compression without bursting. Homeowners must use nylon ropes tied to the corner grommets to center the pillow precisely before securing the pool cover. This product is an absolute necessity for all above-ground pool owners, but it is unnecessary for inground pools with sloped walls that naturally direct ice expansion upward.

Skimmer Guard – Gizzmo Ultra Skimmer Expansion Plug

The skimmer is one of the most vulnerable parts of a pool during winter because water trapped inside its plastic housing will freeze, expand, and crack the housing. Replacing a cracked skimmer often requires excavating the surrounding pool deck, turning a simple freeze into a major construction project. A skimmer guard absorbs this freezing pressure while simultaneously sealing the plumbing line below from incoming water.

The Gizzmo Ultra Skimmer Expansion Plug stands out because it combines a heavy-duty, collapsible plastic tube with integrated dual-size threads (1.5-inch and 2-inch). As ice forms inside the skimmer, the hollow Gizzmo collapses inward to absorb the expansion, preventing the outer skimmer walls from cracking. The built-in rubber gasket at the threads provides an airtight seal, keeping water out of the cleared plumbing lines.

• Threading: Fits standard 1.5″ and 2″ internal skimmer threads
• Length: 16 inches for deep skimmer wells
• Material: High-density, impact-resistant polyethylene

Before screwing the Gizzmo into place, wrapping the threads with Teflon tape ensures a completely watertight seal that won’t seize up by spring. It is vital to choose the correct length; standard pools require the 16-inch version, while shallow skimmers may need a shorter model. This is an essential tool for inground pool owners, but it is not designed for above-ground pools that simply drain the water level below the skimmer mouth.

Expansion Plug – Aquatix Pro Pool Winterizing Plug

Once water is blown out of the pool’s return lines, those pipes must be sealed instantly to prevent water from seeping back in and freezing. Simple plastic threaded caps can leak under pressure or crack in extreme cold, allowing water to slowly refill the lines. Expandable rubber plugs provide a mechanical, pressurized seal inside the pipe that completely blocks moisture and adapts to minor temperature shifts.

The Aquatix Pro Pool Winterizing Plug utilizes a premium, heavy-duty rubber compression sleeve that expands uniformly when the integrated stainless steel wing nut is tightened. This creates a secure, airtight seal deep within the pipe wall that resists slipping, even under significant backpressure. The corrosion-resistant metal components won’t rust or degrade when exposed to harsh winter pool chemicals.

• Sizes Available: Standard sizes from #6 (1″) up to #12 (2″)
• Material: Heavy-duty rubber with stainless steel hardware
• Application: Perfect for return lines, cleaner lines, and skimmer ports

When using these plugs, it is critical to select the exact size matching your pipe diameter, as an oversized plug will not insert deeply enough, and an undersized plug won’t expand sufficiently to seal. Ensure the pipe interior is clean of algae or debris before insertion to prevent slow leaks. This plug is ideal for any pool owner winterizing return jets and suction lines, but it is not a substitute for a threaded skimmer plug in high-freeze zones.

Pool Cover Pump – Wayne WAPC250 Water Removal Pump

Solid pool covers and tarps inevitably collect massive pools of rainwater and melting snow, which can weigh thousands of pounds and drag the cover into the pool. This heavy, stagnant water also attracts mosquitoes and breeds algae, which can easily slip past the cover edges. A reliable cover pump is necessary to automatically remove this accumulation before the weight damages the pool’s top rails or coping.

The Wayne WAPC250 Water Removal Pump is a highly effective choice due to its iCON smart sensing technology, which automatically turns the pump on when water reaches 2.1 inches and off when the surface is dry. This automation prevents the pump from running dry and burning out its motor during freezing nights. The wide, weighted base is designed to resist tipping and features a highly effective debris strainer that prevents leaves from clogging the intake.

• Flow Rate: Up to 3,000 gallons per hour
• Power Cord: 25-foot heavy-duty grounded power cord
• Discharge Connection: Standard 3/4-inch garden hose adapter

Users should place the pump on a small plastic board or flat tile on top of the cover to prevent the pump’s weight from creating a deep dip that strains a single section of fabric. Keep in mind that this pump must be unplugged or stored indoors during periods of sustained sub-zero temperatures when the water on the cover freezes completely solid. This is an essential investment for anyone using solid or tarp-style pool covers, but it is unnecessary for mesh safety covers that drain naturally.

Pool Line Blower – Cyclone Pro Line Bypass Blower

Simply draining the pool below the returns is not enough to protect underground pipes; water trapped in low spots of the plumbing loops will still freeze and rupture the PVC. Standard shop vacs lack the static pressure required to push water out of deep main drains and long plumbing runs. A dedicated pool line blower delivers high-volume, low-pressure air that completely clears every drop of water from the lines.

The Cyclone Pro Line Bypass Blower features a powerful 3.0 HP bypass motor that is specifically engineered to handle the backpressure of pool plumbing without overheating. This multi-stage turbine system creates a continuous blast of air that forces water out of the deepest main drains, leaving the lines dry and safe. Its rugged, impact-resistant plastic casing protects the motor from accidental drops on hard pool decks.

• Motor Power: 3.0 Horsepower bypass motor
• Hose Length: 6-foot flexible hose with 1.5-inch quick-connect fittings
• Weight: 14 pounds for easy portability

This blower requires a standard 120V outlet but draws significant amperage, so running it on a heavy-duty, short extension cord is recommended to prevent voltage drops. It is important to open only one line at a time when blowing out plumbing to maximize the air pressure directed through each pipe. This professional-grade tool is ideal for DIY pool owners who want to avoid paying hundreds of dollars annually for professional closing services, though it does require a basic understanding of pool plumbing valves.

Pool Antifreeze – Splash Pool and Spa Antifreeze

Even after blowing out the plumbing lines, a small amount of residual condensation or slow-leaking ground water can collect in the lowest bends of the pipes. If this trapped water freezes, it can cause hairline fractures that go unnoticed until spring, leading to hidden underground leaks. Filling the plumbing lines with specialized, non-toxic pool antifreeze provides a critical secondary layer of protection against residual moisture.

Splash Pool and Spa Antifreeze is formulated with a high-purity propylene glycol base that is completely non-toxic and safe for both pool equipment and swimmers when the pool is reopened. It is rated to protect pipes from bursting at temperatures as low as -50 degrees Fahrenheit, ensuring ultimate peace of mind in the coldest climates. Unlike automotive antifreeze, this formula will not damage vinyl liners, rubber gaskets, or ABS plastic plumbing.

• Freeze Protection: Burst protection down to -50°F (-46°C)
• Chemical Base: 100% biodegradable propylene glycol
• Volume: Standard 1-gallon bottles

Never use automotive ethylene glycol antifreeze in a pool, as it is highly toxic to humans, pets, and local wildlife, and can ruin pool filtration systems. When pouring antifreeze into the lines, a funnel with a flexible hose is highly recommended to ensure the liquid flows directly into the pipes rather than spilling onto the deck. This product is highly recommended for pool owners in regions with sustained sub-zero winters, but it is generally unnecessary in mild southern climates where hard freezes do not occur.

Cover Water Bag – Swimline Double Water Tube

For inground pools using standard solid tarp covers instead of anchored safety covers, wind is the ultimate enemy. A gust of wind can easily get under a tarp, ballooning it up and dumping accumulated leaves and freezing water directly into the pool. Heavy, water-filled tubes laid along the perimeter of the pool hold the cover edges flush against the deck, preventing wind uplift and sealing out debris.

The Swimline Double Water Tube features a smart double-chamber design that prevents the bag from rolling out of place once filled and laid along the pool edge. Constructed from heavy-gauge vinyl with heat-sealed seams, these tubes are built to withstand the freezing and thawing cycles of winter water. The leak-resistant valves are easy to fill with a standard garden hose and seal tightly to prevent evaporation.

• Configurations: Available in 8-foot and 10-foot lengths
• Chamber Style: Double-tube design to prevent rolling
• Material: Heavy-duty, puncture-resistant virgin vinyl

A vital tip for longevity is to fill these tubes only halfway to three-quarters full; leaving this extra space allows the water inside to expand into ice without splitting the vinyl seams. Space the water bags end-to-end around the entire perimeter of the pool to ensure there are no gaps where wind can catch the cover. These tubes are perfect for budget-conscious inground pool owners using traditional winter tarps, but they are completely redundant for pools equipped with anchored safety covers.

How to Clear Plumbing Lines to Prevent Pipe Bursts

Clearing the plumbing lines is the most critical step of the entire winterization process, requiring methodical execution to ensure no water is left trapped in underground bends. Start by lowering the pool water level to about four to six inches below the lowest return jet or skimmer mouth. Hook up the pool line blower to the skimmer line or the pump’s drain plug opening using a secure threaded adapter.

Turn on the blower and open the valves to isolate one line at a time, beginning with the return lines closest to the equipment pad and working outward. You will see water violently bubble out of the return jets in the pool; keep the blower running until only air is discharging from the line. Quickly insert an expansion plug into the cleared return jet and tighten it securely while the air pressure is still maintaining a dry environment inside the pipe.

Repeat this process for the skimmer and main drain lines. For the main drain, which is located at the bottom of the pool, blow air through the line until a massive geyser of air bubbles erupts from the drain grate. Immediately close the valve at the equipment pad to “air-lock” the line, which keeps water from rising back up into the plumbing from the bottom of the pool.

Crucial Mid-Winter Checks for Frozen Backyard Pools

Winterizing a pool is not a “set-it-and-forget-it” task; seasonal temperature swings and heavy snowstorms require periodic monitoring to prevent issues. Once a month, inspect the pool cover for signs of excessive stress, sagging, or tearing, especially after heavy snowfalls. For solid covers, ensure the cover pump is clear of leaves and operational during thaws to prevent standing water from overloading the pool structure.

Check the positioning of the air pillow in above-ground pools; if a severe storm has shifted the pillow to one side, it will not distribute ice pressure evenly, risking wall failure. If the pillow has lost air, use a manual pump to carefully top it off without removing the cover. For mesh covers, clear any heavy accumulation of leaves that might block water from draining through, which can cause heavy ice sheets to form on top of the mesh.

Finally, take a quick look at the pool water level beneath the cover during mid-winter thaws. If you notice a significant drop in water level, it could indicate a hidden leak in the liner or plumbing, which must be addressed immediately to prevent the heavy cover from collapsing inward. A few minutes of inspection during the coldest months can save thousands of dollars in spring repair bills.

Conclusion

Taking the time to properly close your backyard pool with high-quality gear is the ultimate insurance policy against the destructive power of winter freezes. By sealing the plumbing, balancing the chemistry, and securing a rugged barrier, you protect your investment and guarantee a stress-free spring opening. When the warm weather finally returns, you will be rewarded with crystal-clear water and a pool system that is ready for another season of fun.