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

About 27,600 gal (115.2 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 714 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 Roman

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.

The Roman pool pairs a rectangular body with semicircular ends, a silhouette borrowed from classical baths. You keep an honest swim lane down the middle while the ends soften the geometry and make natural places for steps — a Roman staircase flowing out of the curved end is the signature move.

Open in the 3D designer

Free · no signup · runs in your browser

20 × 40 ft — shown to scale

The numbers, computed

Water surface: 714 sq ft
Water volume: 27,600 gal (115.2 tons)
Perimeter: 102′ 10″
Depth: 3′ 11″–6′ 7″
Excavation approx.: 207 cu yd
Fill time (garden tap): 3 days
Skimmers needed: 3×
Heat pump size: 126,000 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 27,600 gal (115.2 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 714 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 Roman

The numbers, computed

Questions about this plan

Similar pool plans

20 × 40 ft · Rectangular

20 × 40 ft · Rounded rectangle

20 × 40 ft · L-shape

20 × 40 ft · Lazy L

20 × 44 ft · Rectangular

18 × 36 ft · Roman

Go on — put a pool in your garden.