How much water does a 20 × 40 ft pool hold?

About 30,243 gal (126.2 tons of water) at 3′ 11″–6′ 7″ depth — computed from the actual pool outline, not a rule of thumb.

How long does it take to fill?

Roughly 3 days from a standard garden tap (~6.6 GPM). A water delivery service fills it in a few hours.

Is this size right for my garden?

The water surface is 784 sq ft; plan roughly 1.5–2× that footprint including the surrounding deck. Open the plan in the designer and set your own deck margins to see the full footprint.

Can I change the depth or edge type?

Yes — open the plan in the designer and adjust depths, edge system (skimmer, deck-level overflow or raised), finishes and accessories freely.

20 × 40 ft Rounded rectangle

pool plan

Estate pool

An estate-class pool: resort presence at home, with room for swimming, play and lounging at the same time. At this size the supporting decisions matter as much as the basin — plan generous decks, a solid heat source and an automatic cover from day one, because every square metre of water is heated, treated and covered.

A rounded rectangle keeps almost all of the rectangle's swimmable water but rounds the corners into generous fillets. The result reads softer in a garden, is gentler on swimmers, and the corners no longer trap debris the way sharp ones do. It's the shape we default to in the designer.

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20 × 40 ft — shown to scale

The numbers, computed

Water surface: 784 sq ft
Water volume: 30,243 gal (126.2 tons)
Perimeter: 112′ 9″
Depth: 3′ 11″–6′ 7″
Excavation approx.: 227 cu yd
Fill time (garden tap): 3 days
Skimmers needed: 3×
Heat pump size: 140,000 BTU/h

Figures are computed from the sampled pool outline and the plan's depths — the same geometry the 3D designer uses. Excavation includes shell and working allowance; your site conditions may differ.

Questions about this plan

How much water does a 20 × 40 ft pool hold?: About 30,243 gal (126.2 tons of water) at 3′ 11″–6′ 7″ depth — computed from the actual pool outline, not a rule of thumb.
How long does it take to fill?: Roughly 3 days from a standard garden tap (~6.6 GPM). A water delivery service fills it in a few hours.
Is this size right for my garden?: The water surface is 784 sq ft; plan roughly 1.5–2× that footprint including the surrounding deck. Open the plan in the designer and set your own deck margins to see the full footprint.
Can I change the depth or edge type?: Yes — open the plan in the designer and adjust depths, edge system (skimmer, deck-level overflow or raised), finishes and accessories freely.

20 × 40 ft Rounded rectangle

The numbers, computed

Questions about this plan

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Go on — put a pool in your garden.