Floating swimming facility in a harbour at sunrise, steam rising off the water and people on the quayside promenade

Composite swimming facilities — developed in Arendal, Norway

A complete swimming facility. Outdoors, all year.

Aquarious builds swimming facilities in glass-fibre reinforced composite (GRP) — moulded in one piece and floating on the water, or assembled from panels on land. Building outdoors cuts both the investment and the running cost substantially against an indoor facility: it is the building around the pool that costs money, to put up and to run. And a considerably shorter build time than conventional facilities.

Request a pre-project See the solutions

3D visualisation

More pools means more swimmers, greater water safety and better public health

The starting point

Fewer pools — and children who never learn to swim.

Across northern Europe, the public pools built in the 1960s and 70s are reaching the end of their service life at more or less the same time. Refurbishment — in concrete or in steel — is expensive enough that many owners close the facility instead. Norway is a well-documented example of what follows, and the pattern is not unique to it.

41 %

Norwegian ten-year-olds who can swim 200 m

The weakest result since measurements began in 2003, against a national curriculum requirement that every child can. A further 28 % do not know whether they can.

~10

Norwegian pools closing per year

Against 4–8 new builds. A net loss of around 90 facilities over twenty years.

40 h

Instruction needed per child

The Norwegian Swimming Federation's recommendation. Some schools manage ten hours spread over four years.

Swimming-competent ten-year-olds in the Nordic countries

Iceland 96 %

Sweden 92 %

Denmark 79 %

Finland 72 %

Norway 53 %

Sources: Ipsos for the Norwegian Swimming Federation and the Norwegian Society for Sea Rescue (2021) · Norwegian Swimming Federation (2013). Iceland has an outdoor pool in practically every municipality — which is the point of the chart, not a coincidence in it.

The main point

The expensive part is not the pool. It is the building around it.

A conventional indoor pool hall is an air-handling plant with a pool inside it. The building envelope, the ventilation and the dehumidification drive both the investment and the running cost. Remove the building, and most of the cost goes with it — along with the problems it brings.

15–20 %

of the cost of a conventional indoor facility, for a complete outdoor facility. For smaller facilities and standalone pools the saving is greater.

Construction costs have outrun general inflation

The trend is visible wherever it is measured. In Norway, material costs for plumbing work rose 73 per cent and for electrical work 54 per cent between 2019 and 2023, while consumer prices rose 22 per cent from 2019 to 2024. The gap has not closed: construction costs rose a further 3.8 per cent in 2024 and 4.3 per cent in 2025, against a predictable pre-pandemic average of around 2.7 per cent a year. Piping and electrical work are precisely the line items that dominate a pool budget — water treatment, ventilation and building services. A project costed before the pandemic is a different project today.

Lower energy use than indoors

An indoor pool hall has to heat and dehumidify a large volume of air all year round. Documented consumption runs at 3 000–4 000 kWh per square metre of water surface per year. Outdoors that entire load disappears. What remains is heating the water — and the floating facilities come with an integrated sea-water heat plant. At a sea temperature of two degrees Celsius, in midwinter, one kilowatt-hour of electricity yields around four and a half kilowatt-hours of heat.

Air without chloramines

Trichloramine is heavier than air and settles in a layer just above the water, exactly where swimmers breathe. Indoors this is locked in: ventilation is deliberately not directed down at the water, because that would increase evaporation and energy use. Air quality and the energy bill are in direct conflict, and energy wins. Outdoors that trade-off does not exist.

No moisture damage to the building

A large share of pool halls develop moisture damage in the structure. With no building envelope for condensation to migrate into, the whole damage mechanism disappears — and with it the maintenance it generates.

Cost inflation: Statistics Norway, sub-indices for materials, processed by Prognosesenteret. Measurement periods as stated in the text. Energy figures: NTNU / Gode idrettsanlegg. Moisture damage: Byggforskserien 552.315. The cost ratio is Aquarious' own experience figure and is documented in the pre-project.

Two solutions

One technology, two ways to build.

The site decides. If you have sea, river or harbour basin, you avoid ground works altogether. If you have dry land, the facility is assembled on site from prefabricated elements.

3D visualisation

Floating

Single-moulded pool on the water

The hull is vacuum-infused in one operation. No joints, no sealant lines, no ground works. The facility is towed into place and moored — and can be relocated if the harbour changes around it.

Pool size: 25 × 12.5 m, or to requirement
Construction: Vacuum-infused sandwich
Ground works: None
Heating: Integrated sea-water heat plant
Build time: About one year
Transport: Deck cargo and tow

About floating facilities →

3D visualisation

Land-based

Panel-built pool on a site

Built upwards from flat ground — asphalt, concrete or compacted gravel — with no excavation and no blasting. The elements are bonded under pressure and vacuum, stacked flat for shipping by sea or road, and assembled on site.

Pool size: 25 × 12.5 m, or to requirement
Construction: Prefabricated sandwich panels
Excavation: None
Heating: Boreholes, waste heat or district heating
Build time: About one year
Transport: Stacked flat, by sea or road

About land-based facilities →

The technology

The material comes from boatbuilding and offshore.

Glass-fibre reinforced composite (GRP) has been used in boat hulls for some seventy years, and in subsea structures on the continental shelf for decades. Seawater degrades most building materials, and a boat hull stands in constant UV radiation on top of it. Composite handles both. We build pools on the same principles.

Built for the outdoor environment

Chlorinated water attacks reinforcement steel in concrete and weld zones in steel. UV radiation degrades many materials in the open. Composite resists both.

No tiles to replace

The surface is part of the laminate, not a layer bonded on top. The most common maintenance item simply disappears.

Low self-weight

Less foundation work, simpler transport, and facilities on sites concrete cannot reach.

Insulating core of recycled plastic

Where a steel shell conducts heat outwards, the sandwich core insulates. It is made from recycled plastic, and lower heat loss means a lower energy bill every day the facility stands.

Smaller climate footprint

Measured across the service life, a GRP pool comes out ahead of concrete and steel. Far less material mass, a recycled core, no surfaces to replace, and a fraction of the transport weight.

70 years

of glass-fibre boats in the sea. Most of them are still floating — and it is the same material technology that sits under our pools.

Owners and operators

Who we build for.

The engineering is rarely the hard part. What decides whether a project happens is ownership, procurement rules and public funding — and those are national. Norway has one set of schemes, your country will have another. We work out what applies to you as part of the pre-project rather than guessing at it here.

Municipalities and local authorities

Replace a facility nearing the end of its life

We come in early, while the need is still being assessed, and provide the figures an administration needs before the case goes to political decision.

Condition assessment against refurbishment cost
Documentation for a compliant procurement process
Whole-life cost, not just capital expenditure
Technical documentation for grant applications

Talk to us →

Sports clubs and swimming clubs

Build and run your own facility

A club that owns its facility controls its own training hours. In several countries clubs also have access to funding routes a municipality does not.

Technical documentation for funding applications
Support through the application process
Dialogue with the municipality on site and lease
Dimensioning against actual club use

Talk to us →

Property developers

Make the pool part of the scheme

A swimming facility raises the appeal of a residential area, and can be operated with the municipality as tenant. A floating facility takes up no plot area at all.

Site assessment across an existing portfolio
Lease model with a public counterparty
Turnkey delivery — you own and operate
Ownership structure and what it means for funding

Talk to us →

Reference

The facility that became Aquarious.

Arendal Sjøbad was built as a public research and development contract, with the municipal port authority Arendal Havn KF as client, designer and contractor. Our managing director was project manager and our chief designer did the design. CSUB engineered and fabricated the pool, and is our fabrication partner today.

Aquarious was established to take this proven concept to other locations. We are happy to show the structure, the water quality and the operation to anyone interested.

Arendal Sjøbad, the floating swimming facility in Arendal guest harbour on a summer morning, with swimmers in the pool, boats at the quay and the town behind — Facility **Arendal Sjøbad** Client **Arendal Havn KF** Delivered as **public R&D contract** Status **In operation** Photo: Aquarious

First step

Start with a pre-project.

Before anyone takes a position on a facility costing tens of millions, you need something to decide on. The pre-project is a defined, fixed-price deliverable that provides exactly that — without committing you to build.

Need and dimensioningWho will use the facility, and how large does it have to be?
Location and site conditionsAssessment of the proposed site or harbour area.
Cost and energyInvestment, operating cost and energy budget across the service life.
Ownership and fundingWhich routes are actually open to you in your country, and what they require.

Pre-project

From NOK 50,000

Duration 2–4 months Non-binding Yes

Request a pre-project

Price and scope apply to projects in Norway. Outside Norway the scope of work differs — local regulation, permitting and site conditions all feed into it — so both scope and price are set on enquiry. Not there yet? Call us, or ask for the company presentation by email.