21 x 21 Ft Swimming Pool Ground Cloth - Heavy Duty Ground Mat

In this review of the 21 x 21 ft swimming pool ground cloth the bottom line is simple: this tarp is best for owners of above ground pools up to 16 ft who need an inexpensive, large protective layer to guard liners from rocks and roots. The reviewer found the sheet effective at creating a smoother base and preventing punctures, and it stands out for its size and ease of cleaning. It is not a premium rubber underlay, but for many seasonal pool owners the combination of coverage and low weight makes it a sensible protective option.

Key Features

• Large coverage: The 21 ft by 21 ft size is roomy enough to cover the ground under most above ground pools up to 16 ft, reducing exposed edges and gaps.
• Thin, protective layer: The 0.2mm PE thickness offers a barrier against small stones and roots so pool liners face fewer cuts and punctures.
• Durable PE material: Made from heavy-duty PE plastic that is tough and flexible, suitable for framed pools and inflatable top ring pools.
• Finished edges with button holes: Reinforced-looking edges with button holes improve lay-flat performance and make the tarp easier to align and secure.
• Easy to maintain: The surface can be rinsed and soaped for quick cleaning and the cloth folds for compact storage between seasons.
• Multi-use: Beyond pools the tarp works for camping, covering boats or cars, and protecting outdoor items from dust and moisture.

Who It's For

The ground cloth is aimed at budget-conscious pool owners who need a large, lightweight underlay to reduce the risk of liner damage from surface debris; it suits seasonal pools, renters, and families who prefer simple setup and easy storage. It is also a good choice for people who want a versatile tarp that doubles for camping or covering outdoor gear.

People who want a thick, long-term industrial mat or expect heavy abrasion resistance should look elsewhere, because the material is a thin PE sheet rather than a dense foam or reinforced rubber underpad. Those needing a permanent solution for rough ground may prefer a heavier commercial liner.

Pros & Cons

Pros

• Large 21 ft x 21 ft size provides ample coverage for pools up to 16 ft.
• Affordable and lightweight, easy to carry, lay out and fold for storage.
• Simple to clean with soap and water and resistant to common outdoor grime.
• Edges with button holes help keep the cloth in place and give a neater appearance.

Cons

• The 0.2mm thickness is thin; some users report it feels paper-thin and may tear under severe stress.
• Material quality and long-term durability are mixed, so it may not endure heavy abrasion or sharp objects indefinitely.

Specifications

Product type	Swimming pool ground cloth / tarp
Size	21 ft x 21 ft
Fits pools up to	16 ft
Material	PE plastic
Thickness	0.2 mm
Edge detail	Button holes on edges

Our Verdict

The 21 x 21 ft ground cloth is a practical, low-cost protector for above ground pools up to 16 ft, offering wide coverage, easy cleaning and simple storage. It delivers good value for seasonal or light-duty use, but buyers seeking a thick, heavy-duty underlay for rough terrain should consider sturdier alternatives.

Frequently Asked Questions

Will this fit my 12 ft above ground pool?
Yes, the 21 ft x 21 ft size gives plenty of overlap for pools up to 16 ft, so it will easily fit a 12 ft pool.

Can it be used on rough or rocky ground?
It provides a barrier against small stones and roots but the 0.2 mm PE is thin, so for very rocky ground a thicker underpad is recommended.

How do you clean and store it?
The PE surface can be rinsed and washed with soap, then folded and stored dry to save space between seasons.