Blue Wave 21-Ft Round Above Ground Pool Winter Cover, 8-Year

Yes, for the right buyer. The Blue Wave 21-Ft Round Above Ground Pool Winter Cover, 8-Year ranks #6 in our Best Pool Covers list. Its biggest strength: elastic cable system is faster to install than water bags around the full perimeter. The main caveat: not weight-rated, same as any winter tarp, don't let kids or pets walk on it.

The main trade-offs owners and reviewers point to: not weight-rated, same as any winter tarp, don't let kids or pets walk on it; shorter warranty than the Arctic Armor 15-year line at a similar price point; cable-and-winch tensioning loosens over the season and needs occasional re-tightening.

8-year warranty, 21-ft round fit, Elastic cable-and-winch tensioning system and Woven polyethylene tarp.

Worth comparing: Blue Wave NS420 16x32 Ft Rectangle Solar Pool Cover 12-Mil Blue, Pool Mate 18x33 Ft Blue/Silver Deluxe Oval Solar Cover 8-Mil and Robelle 20x40 Ft Heavy Duty Green Winter Pool Cover for Inground Pools. Each ranks near it in our research for a slightly different buyer.

It's sold on Amazon. Prices and stock change often, so check the current listing before you buy, our link takes you straight to it.

Above-ground pool covers hook to the top rail of the pool wall using an elastic cable or winch-and-cable system, so the cover only needs to match the pool diameter plus a few inches of overlap. Inground pool covers anchor to the surrounding deck, which sits at ground level, so the cover has to extend well past the water's edge onto the coping and deck itself. Standard inground winter covers add a 4 to 5-foot overlap on every side (a 20x40 pool needs roughly a 25x45 cover), and safety covers are measured to the exact deck anchor points, which is why safety covers are far more often custom-fit than stock-sized. Buying an above-ground-style cover for an inground pool will leave gaps at the edges regardless of how it is anchored.

That depends entirely on who has access to the pool. If small children, pets, or anyone unable to swim can reach the pool area unsupervised, a winter tarp is not adequate protection, it is not weight-rated and can fail catastrophically under a person's weight, especially once pooled rainwater or snowmelt sits on top of it. Local and state codes in many areas require a compliant barrier (fence, cover, or both) around residential pools; an ASTM F1346-rated safety cover satisfies the cover portion of that requirement in jurisdictions that allow it. If the pool area is already fully fenced with a self-latching gate and unsupervised access isn't a realistic risk, a winter tarp is a reasonable and much cheaper choice for keeping debris and sun out during the off season.