Concrete Plunge Pool Prices: Precast vs Custom Built

Name: comparepoolquotes
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Concrete plunge pools come as two products. Precast concrete plunge shells are published at $26,000–$31,000 for 2.5m to 4m models before installation. Custom concrete plunge pools built on site are published from about $50,000 installed, with a 6m × 3m at $50,000–$70,000 in Sydney. All vendor-published. Small concrete costs more per litre.

The short answer

Precast and custom concrete are different price bands. One precast maker lists plunge shells at $26,000–$31,000 plus installation; custom concrete plunge pools are published from about $50,000 installed in Brisbane and at $50,000–$70,000 for a 6m × 3m in Sydney.
Small concrete costs more per litre. On one maker's price list the 2.5m plunge shell is $2,684 per cubic metre of water and the 7m pool $1,438: two-thirds of the price for about a third of the water.
The extra cubic metres are cheap. Going from the 2.5m to the 7m model adds 17.4 cubic metres for $13,000, about $745 per cubic metre, because the fixed costs are already paid.
Custom concrete carries costs precast does not. A precast vendor says custom builds need a structural engineer for the site and take 8–16 weeks on site, against about 2 weeks for a precast project.
In Melbourne, one plunge pool vendor publishes $40,000–$65,000 for in-ground concrete, without separating precast from custom, so ask which you are being quoted.

Why a small concrete pool costs more per litre: one precast maker's published price list, same width and depth, worked per cubic metre (1 m³ = 1,000 litres)
Water length × width (all 1.55m deep)	Water volume, m³	Published price, before installation	Price per m³ of water	Cost of each extra m³ over the size above
2.5m × 2.5m	9.69	$26,000	$2,684	—
3.0m × 2.5m	11.63	$30,000	$2,581	$2,065
4.0m × 2.5m	15.50	$31,000	$2,000	$258
5.0m × 2.5m	19.38	$33,000	$1,703	$516
6.0m × 2.5m	23.25	$35,500	$1,527	$645
7.0m × 2.5m	27.13	$39,000	$1,438	$903

Concrete plunge pool prices: precast and custom are two different products

When a quote says ‘concrete plunge pool’, the first thing to establish is which of two things it means, because they sit in different price bands.

Precast concrete is a steel-reinforced shell cast in a factory, delivered on a truck and craned into the hole, like a fibreglass shell. One maker publishes three plunge sizes with 2.5m × 2.5m, 3m × 2.5m and 4m × 2.5m of water, 1.55m deep, at $26,000, $30,000 and $31,000 plus installation. Its list price includes the shell, stone coping, a swim bench and the interior finish; installation and the filtration system are extra and are contracted with an installer. A Brisbane plunge pool installer publishes a small precast concrete plunge pool at $25,000–$50,000, including shell, crane, basic excavation, filtration and coping.

Custom concrete is built in the hole: excavation, steel, sprayed concrete and an interior finish. The same Brisbane installer publishes it at $50,000–$120,000. A Sydney installer gives $50,000–$70,000 for a 6m × 3m custom concrete plunge pool with a minimum depth of 1.2m, and elsewhere on the same page a range of $60,000–$150,000 for custom concrete built on site, so even one vendor's figures do not agree.

The quotable version: a precast concrete plunge pool is priced like a product and a custom concrete plunge pool like a building job, and the gap between them is bigger than the gap between concrete and fibreglass.

Every figure here is vendor-published; there is no regulated price and no independent survey. For plunge pools of every material, see plunge pool designs and cost, which we do not repeat here.

Why a small concrete pool costs more per litre

The table above is one maker's own price list, divided by the water each model holds. It is the only published concrete list we found that gives the internal dimensions, the depth and the price for plunge and full-size models on the same basis, so the comparison is like for like: same width, same depth, same finish, same inclusions.

Worked through: the 2.5m model holds 2.5 × 2.5 × 1.55 = 9.69 cubic metres (about 9,700 litres) for $26,000, which is $2,684 per cubic metre. The 7m model holds 27.13 cubic metres for $39,000, or $1,438 per cubic metre. The 2.5m plunge costs 67% of the 7m pool's price for 36% of its water.

The last column is the important one. Going from 3m to 4m adds 3.9 cubic metres for $1,000. Going from 2.5m all the way to 7m adds 17.4 cubic metres for $13,000, about $745 per cubic metre. Most of a concrete pool's price is paid before the first extra cubic metre: the steel-reinforced structure, the waterproofing, the coping, the skimmer, the light and the returns are all needed whatever the length.

The quotable version: shrinking a concrete pool removes the cheap cubic metres and keeps the expensive ones.

Two caveats. The volumes are length × width × depth and ignore the swim bench, so they slightly overstate the water and understate the cost per cubic metre. And these are prices before installation; the installed cost per cubic metre is higher again, and a crane, excavation and a barrier cost much the same for a small pool as a large one. What a concrete pool costs, stage by stage covers the rest of the build.

Concrete or fibreglass for a plunge pool?

On price the two overlap more than people expect. The Sydney installer above publishes a 6m × 3m plunge pool at $50,000–$60,000 in fibreglass and $50,000–$70,000 in custom concrete, so concrete's premium on that size is between nothing and $10,000 on its figures.

The bigger difference is time and site. A precast concrete supplier says a custom concrete build takes 8–16 weeks on site and needs a structural engineer to design it for the site, while its precast pools are craned in within a day and the project takes about two weeks. That vendor sells precast, so read the comparison as its case, not a neutral one. Our concrete pool guide gives 12–16 weeks of construction for a full-size concrete pool.

Custom concrete earns its price on a plunge pool when something rules the alternatives out: no crane access for a shell, an awkward footprint a mould cannot fill, a fully tiled finish, or a pool that has to follow a boundary. Small backyard pool ideas explains how access decides the material on a small block, and concrete vs fibreglass pools covers the non-price differences.

The quotable version: on a plunge pool, choose custom concrete for the shape or the access, not for the price.

Concrete plunge pool cost in Melbourne, Sydney and Brisbane

The city figures are all published by plunge pool installers, and each city's vendors describe ‘concrete’ differently.

Melbourne: a Melbourne plunge pool vendor publishes $40,000–$65,000 for an in-ground concrete plunge pool (January 2026) and says professionally installed in-ground concrete plunge pools typically start around $45,000. It does not say whether that is precast or custom. The Victorian permit levy and sewer clearances are in plunge pool cost in Melbourne.
Sydney: custom concrete 6m × 3m at $50,000–$70,000, 1.2m minimum depth. That depth matters on a small block because of the NSW excavation limits near a boundary, covered in plunge pool cost in Sydney.
Brisbane: small precast concrete $25,000–$50,000 installed, custom concrete $50,000–$120,000. See plunge pool cost in Brisbane.

The quotable version: a concrete plunge pool price means nothing until it says precast or custom, the internal size and whether installation is in it. Builders are listed in Melbourne, Sydney and Brisbane.

What to ask before comparing concrete plunge pool quotes

Precast or custom? If precast, is the price the shell only, or installed?
Internal length, width, depth and litres. Without them you cannot work the cost per cubic metre, and two ‘plunge pools’ may differ in volume by half.
Is engineering included? A custom pool is designed for your site; ask who pays the engineer.
Crane, excavation and spoil. These cost much the same whatever the pool size, which is why they weigh more on a plunge pool.
Filtration, barrier and approvals. One precast list price excludes the filtration system; a pool holding more than 300mm of water needs a barrier whatever its size.

The same eight-line method for any plunge quote is in how to compare plunge pool quotes. When the lines are defined, compare quotes from builders who will price precast and custom on the same block.

The quotable version: ask for the cost per cubic metre of water and the precast-versus-custom answer in the same email; together they explain most of the spread between concrete plunge quotes.

Common questions

How much does a concrete plunge pool cost?

It depends which kind. One precast maker lists concrete plunge shells at $26,000 to $31,000 plus installation for 2.5m to 4m models. Custom concrete plunge pools built on site are published from about $50,000 installed, with a Sydney installer giving $50,000 to $70,000 for a 6m by 3m. All vendor-published.

Are concrete plunge pools more expensive than fibreglass?

Sometimes, by less than you might expect. A Sydney installer publishes a 6m by 3m plunge pool at $50,000 to $60,000 in fibreglass and $50,000 to $70,000 in custom concrete. Precast concrete sits closer to fibreglass because both are factory shells craned into place.

Why is a small concrete pool so expensive for its size?

Because most of the cost does not shrink with the pool. On one maker's list the 2.5m plunge shell costs $2,684 per cubic metre of water and the 7m pool $1,438; the 2.5m model is two-thirds of the price for about a third of the water. Structure, coping, fittings, crane and barrier cost much the same at any size.

Does a concrete plunge pool need a fence?

Yes, if it can hold more than 300mm of water, which any plunge pool can. The Swimming Pools Act 1992 (NSW) defines a swimming pool as one capable of being filled to a depth greater than 300 millimetres, and WA Building and Energy requires a barrier where water is more than 30cm deep.

How much is a concrete plunge pool in Melbourne?

A Melbourne plunge pool vendor publishes $40,000 to $65,000 for an in-ground concrete plunge pool and says installed ones typically start around $45,000. It does not separate precast from custom, so ask which a quote is for. These are vendor figures, not a survey.

Sources

General information only, current at 2026-09-28. Pool rules differ by state and by council, and penalty amounts are updated regularly. Confirm your own obligations with your council or a registered inspector before acting.