9 Essential Tools to Winterize an Above Ground Pool for Freezing Climates

As autumn leaves begin to turn and the evening breeze carries a distinct chill, the backyard swimming season draws to an inevitable close. Failing to prepare an above ground pool for freezing temperatures can result in buckled walls, torn liners, and ruptured plumbing by spring. Having the right tools on hand transforms this demanding chore into a straightforward weekend project that safeguards your recreational investment for years to come.

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Why Freezing Temperatures Require Proactive Pool Prep

Water expands by approximately nine percent when it freezes, exerting immense outward pressure on anything containing it. In an above ground pool, this expansion can easily warp the steel walls, split the vinyl liner, or crack the plastic skimmer assembly. Without proactive measures, a single severe freeze can turn a fully functional pool into a pile of scrap metal and ruined vinyl.

Furthermore, stagnant water trapped in lines over the winter becomes a breeding ground for algae and bacteria. When temperatures drop, undrained pipes or hoses will retain water that freezes, expands, and splits the plumbing lines. Fixing these issues in the spring is incredibly costly, time-consuming, and entirely preventable with the right winterization strategy.

Proper preparation is not about keeping the pool ready for swimming, but about structural survival. By managing ice expansion, sealing off plumbing lines, and securing the pool cover, you ensure the structure withstands the brute force of winter. Taking these steps guarantees a smooth, low-cost opening when warm weather returns.

Pool Cover – Blue Wave Bronze Round Above Ground Cover

A solid pool cover is the first line of defense against winter debris, blocking sunlight to stop algae growth and keeping leaves out of the water. Without a reliable cover, winter winds will fill the pool with organic matter that decays, stains the liner, and ruins the water chemistry. A quality cover must withstand freezing temperatures, heavy snow loads, and constant wind whipping.

The Blue Wave Bronze Round Above Ground Cover stands out due to its heavy-duty polyethylene construction and rugged scrim count. It features heat-sealed seams that prevent water from dripping through, keeping dirty precipitation separate from your clean pool water. The cover also includes a vinyl-coated cable and a metal winch system to secure it tightly around the pool perimeter.

• Material: Woven polyethylene
• Overlap: 4-foot overlap (crucial for pools using air pillows)
• Warranty: 8-year limited warranty
• Color: Forest green top, black underside to block light

When choosing a size, always purchase a cover that accounts for the pool’s diameter plus a generous overlap. If the pool is 24 feet round and uses an air pillow, a cover with a 4-foot overlap is necessary to prevent the cover from being pulled too tight. This cover is perfect for budget-conscious owners needing dependable protection, but it is not designed to support the weight of pets or children.

Air Pillow – Swimline Ice Equalizer Vinyl Pillow

When ice forms on the pool surface, it expands outward, applying massive lateral pressure directly to the pool walls. An air pillow sits in the center of the pool, acting as a compression cushion that absorbs this ice expansion. As the ice pushes inward, the pillow compresses, relieving stress on the pool walls and preventing structural collapse.

The Swimline Ice Equalizer Vinyl Pillow is the ideal choice because of its heavy-gauge vinyl composition and reliable air valves. Unlike cheap, thin pillows that deflate under pressure, this model is built to survive the crushing weight of shifting ice sheets. Its reinforced grommets on the corners make it easy to tie off and center in the middle of the pool.

• Material: Heavy-duty 16-gauge vinyl
• Common Sizes: 4×4 feet, 4×8 feet, and 4×15 feet
• Best For: Round or oval above ground pools in freezing climates

For proper installation, only inflate the pillow to 60 to 80 percent of its capacity. Over-inflating the pillow leaves no room for compression, which can cause it to pop under the weight of freezing ice. This tool is absolutely essential for anyone in hard-freeze regions, though pool owners in mild climates without freezing conditions can safely skip it.

Cover Pump – Little Giant APCP-1700 Automatic Pump

Rainwater and melting snow quickly accumulate on top of pool covers, creating massive weight that can pull the cover off or damage the pool walls. A cover pump automatically removes this pooling water, keeping the cover light and preventing stress on the structure. Leaving standing water on a cover also invites nesting pests and creates a safety hazard.

The Little Giant APCP-1700 Automatic Pump is the standard for this task because of its automatic water-sensing switch. It activates when water reaches a depth of two inches and shuts off once the surface is dry, requiring zero manual monitoring. The integrated intake screen prevents leaves and twigs from clogging the impeller, ensuring continuous operation.

• Flow Rate: Up to 1,700 gallons per hour
• Power Cord: 25-foot heavy-duty power cord
• Discharge Connection: Standard 3/4-inch garden hose thread

Keep in mind that this pump requires a nearby GFCI-protected outdoor outlet to operate safely. It should be removed from the cover during periods of deep freeze, as ice can damage the internal components of any submersible pump. This pump is a lifesaver for busy pool owners, but may be overkill for dry climates with minimal winter precipitation.

Winterizing Kit – In The Swim Deluxe Closing Kit

Closing a pool with unbalanced or untreated water is a recipe for a dark, algae-ridden swamp in the spring. A winterizing chemical kit provides a pre-measured combination of chemicals designed to prevent algae growth, eliminate organic contaminants, and protect pool surfaces from staining over the winter. Using a complete kit removes the guesswork from seasonal chemical balancing.

The In The Swim Deluxe Closing Kit is a top-tier choice because it contains premium, slow-releasing winter chemicals that work throughout the cold months. The kit includes a copper-free winterizer, non-chlorine shock, a stain rust and scale preventer, and a winter chemical floater. These components work together to keep the water clear without bleaching or damaging the pool’s vinyl liner.

• Pool Volume Capacity: Up to 15,000 gallons (larger sizes available)
• Kit Contents: Winterizer liquid, Winter Stain Away, Chlorine-Free Shock, Winter Floater
• Compatibility: All pool types, especially vinyl above ground liners

Before adding the kit, ensure the pool water is clean and properly balanced. The non-chlorine shock should be dissolved and distributed evenly, and the winterizer should be poured directly into the water with the filter running. This kit is perfect for those seeking convenience, but advanced pool owners who prefer to mix their own chemical cocktails may find individual purchases more cost-effective.

Skimmer Cover – Aquador 1090 Winter Skimmer Lid

Traditionally, winterizing required draining the pool water below the skimmer mouth to prevent water from entering the filtration system. Draining the pool this low puts excessive stress on the pool walls and can cause vinyl liners to shrink or crack. A skimmer cover seals the skimmer faceplate airtight, allowing you to keep the pool water at its normal operating level.

The Aquador 1090 Winter Skimmer Lid features a snap-on plastic faceplate design that provides a completely watertight seal. Once the permanent Aquador faceplate is installed in place of your standard skimmer faceplate, winterizing is as simple as snapping on the durable plastic lid. This eliminates the need to disconnect hoses or drain thousands of gallons of balanced pool water.

• Model Compatibility: Standard U.S. skimmers (Aquador 1090 fits standard 6-inch skimmers)
• Installation: Replace existing faceplate once, snap lid on annually
• Material: UV-stabilized, impact-resistant plastic

You must ensure that your current skimmer matches the exact dimensions and screw pattern of the Aquador 1090 before ordering. The initial installation requires removing the old faceplate and screws, which can be slightly intimidating for beginners, but the long-term time savings are unmatched. This tool is a must-have for anyone looking to simplify their annual closing routine.

Expansion Plug – Hayward SP1022C Rubber Plug

After sealing the skimmer, the return lines (where water pumps back into the pool) must also be blocked to prevent water from entering the plumbing lines. Water trapped inside these return lines will freeze, expand, and rupture the hoses or hard PVC pipes. An expansion plug is a simple tool that creates a watertight seal inside the return fitting.

The Hayward SP1022C Rubber Plug features a tapered neoprene rubber body and a non-corrosive nylon wing nut. As you tighten the wing nut, the rubber body expands inside the pipe, creating a heavy-duty seal that resists freezing pressure. The nylon hardware ensures the plug will not rust or seize, making it easy to remove when spring arrives.

• Size: 1.5-inch thread diameter (fits standard pool returns)
• Material: Neoprene rubber with nylon wing nut and bolt
• Application: Return lines, cleaner lines, and skimmer drains

Ensure you thoroughly clean any algae or debris out of the return fitting before inserting the plug to guarantee a proper seal. Hand-tighten the wing nut until snug; over-tightening with tools can crack the plastic return fitting. This plug is an absolute necessity for any pool owner in freezing climates, while those in tropical climates have no need for plumbing plugs.

Cover Seal – Blue Wave Winter Cover Shield Wrap

High winter winds can easily get under the edges of an above ground pool cover, causing it to billow, rip, or blow away entirely. A cover seal is a specialized plastic wrap that wraps around the perimeter of the pool, sealing the gap between the cover and the pool wall. This blocks wind from getting underneath, protecting both the cover and the pool structure from wind damage.

The Blue Wave Winter Cover Shield Wrap is made from a high-density, UV-resistant stretch film that clings tightly to itself. Unlike regular shipping wrap, this film is engineered to withstand extreme cold and intense winter sunlight without degrading or losing its grip. It holds the cover flush against the pool wall, preventing wind flapping and stopping dirt from blowing under the edges.

• Roll Length: 800 feet (covers multiple seasons or multiple wraps)
• Width: 8 inches
• Material: Heavy-duty, UV-inhibiting stretch polymer

Using this wrap requires wrapping the pool perimeter at least three to four times while pulling the film tight. It is a single-use product, meaning you will need to cut it off and discard it when opening the pool in the spring. This wrap is highly recommended for windy, open-concept backyards, but is less critical for pools heavily shielded by fences or dense landscaping.

Cover Clips – Swimline Above Ground Locking Wall Clips

While cables and winches secure the cover perimeter, they can still allow the cover to slide or flap in strong gusts. Cover clips attach the pool cover directly to the pool’s top metal rail, providing extra anchor points across the entire circumference. This mechanical grip prevents wind from getting under the cover, taking the strain off the cable system.

The Swimline Above Ground Locking Wall Clips utilize a two-piece locking design that clamps down securely on both the cover and the pool wall rail. Made from durable, freeze-resistant plastic, these clips will not crack or lose their grip in sub-zero temperatures. They slide easily onto the metal rail, providing a tight hold that keeps the cover perfectly centered.

• Quantity: Available in packs of 10, 20, or 30 (use 2 per top rail section)
• Compatibility: Standard metal top rails
• Material: Freeze-proof ABS plastic

These clips are designed specifically for standard metal top rails and will not fit on extra-wide resin rails or soft-sided temporary pool frames. For maximum wind protection, space the clips evenly around the pool, particularly on the side facing the prevailing winter winds. They are perfect for budget-conscious owners seeking an extra layer of wind insurance, but useless for pools without rigid metal top rails.

Leaf Net – Robelle Round Above Ground Leaf Cover

If your backyard is surrounded by trees, autumn leaves can pile up on your winter cover, creating a heavy, rotting mess. A leaf net is a lightweight mesh cover that is installed directly on top of the winter cover before the leaves fall. Once the trees are bare, you simply peel the leaf net off, instantly removing all the debris and leaving a clean cover underneath.

The Robelle Round Above Ground Leaf Cover is crafted from a durable polyethylene mesh with a tight weave that catches even small leaves and pine needles. It features a heavy-duty binding and a vinyl-coated cable with a winch to keep it secure. The open-mesh design allows rainwater to pass through easily, preventing the net from becoming too heavy to lift.

• Material: High-density polyethylene mesh
• Overlap: 3-foot overlap
• Primary Function: Debris and leaf removal before winter freezes

It is critical to remove the leaf net before the first major freeze or snowfall. If left on during a freeze, the wet leaves will freeze solid to the winter cover, making the net impossible to remove and potentially tearing both covers. This is a must-have time-saver for wooded properties, but a redundant expense for open lawns with no nearby deciduous trees.

How to Properly Balance Pool Chemistry Before Closing

The secret to a crystal-clear spring opening starts days before you actually put the winter cover on the pool. It is critical to adjust your water chemistry—specifically pH, total alkalinity, and calcium hardness—to ideal levels. Improperly balanced water during the winter can corrode pool equipment, etch plaster, or cause calcium deposits to scale along the vinyl liner. Aim for a pH level of 7.2 to 7.6, total alkalinity between 80 and 120 ppm, and calcium hardness between 200 and 400 ppm.

Once the basic parameters are balanced, add a heavy dose of pool shock to sanitize the water and eliminate any microscopic organic matter. Do not close the pool immediately after shocking; instead, let the chlorine level return to normal (around 1 to 3 ppm) over several days. Super-high chlorine levels can degrade the vinyl liner and prematurely wear out the winter cover. After the chlorine level stabilizes, add your winter algaecide and stain preventer to protect the pool during its long hibernation.

Crucial Inspections to Perform Throughout the Winter

Winterizing an above ground pool is not a “set-it-and-forget-it” project. Throughout the cold season, make a habit of checking on the pool cover, especially after major storms or high wind events. Ensure that the cover pump is clear of ice and debris so it can efficiently drain accumulating rainwater and melted snow. If a heavy blanket of snow accumulates on the cover, use a soft-bristled broom to gently push it off, protecting the pool structure from excessive weight.

Additionally, inspect the tension of the winter cover cables, cover clips, and cover seal wrap. Shifting ice can sometimes cause the air pillow to move or lose air, so monitor the center of the cover to ensure the pillow remains functional. Look around the external perimeter of the pool wall for any signs of bowing, leaking, or ice accumulation on the outside of the liner. Catching a small leak or a loose cable early in the winter can prevent catastrophic pool failure before the spring thaw arrives.

Conclusion

By investing in the right tools and staying proactive through the coldest months, you protect your above ground pool from the destructive forces of freezing winter weather. Taking the time to properly seal plumbing, balance chemistry, and secure the cover ensures a stress-free spring opening. When the warm weather finally returns, your pool will be clean, safe, and ready for another season of backyard fun.