Indoor pool design

An indoor pool is not a pool with a roof over it. It is a permanently humid room that must be dehumidified, ventilated and protected from chloramines 365 days a year.

The most expensive mistake in an indoor pool is designing it as a pool rather than as a climate installation. Without proper dehumidification, condensation starts at the joinery, moves to the ceiling void and ends in the structure.

We design the whole enclosure: envelope, dehumidification, water treatment, acoustics and material specification able to survive a chlorinated atmosphere.

The balance you have to hold

Air warmer than water

Air is kept 1-2 °C above water temperature to limit evaporation. Reversing that relationship drives up both energy use and condensation.

Relative humidity 55-65 %

Below that, evaporation and running cost rise. Above it, condensation and corrosion appear on the envelope.

Dedicated dehumidification

With heat recovery. It is what makes the running cost of a covered pool viable at all.

Night-time thermal cover

Cuts evaporation dramatically during the unused hours, which are the majority of the year.

What survives chlorine

AISI 316 stainless steel

In a chlorinated atmosphere, 304 pits within a few years. Fixings, anchors and grilles must be 316 or non-metallic.

Thermally broken joinery

With low-emissivity glazing and dew point control along the glazed perimeter.

Wet slip-resistant flooring

Class 3 around the pool surround. Natural stone needs a chlorine-compatible stain treatment.

Accessible, resistant ceilings

Powder-coated aluminium or specified treated timber. Standard plasterboard does not survive the humidity cycle.

Acoustics, light and actual use

Reverberation

A room of water, glass and ceramics echoes like a sports hall. Humidity-rated absorbent surfaces are essential.

Daylight without glare

Orientation and solar control so reflection off the water does not make the space unusable at midday.

Adjacent dry zone

Changing, shower and towel storage outside the wet enclosure extend the life of everything else.

Accessible plant room

Filtration, dehumidifier and water treatment need their own ventilated, accessible space.

Indicative ranges

Design and supervision fees. Pool shell, filtration and dehumidification are quoted with specialist contractors.

ScopeIndicative range
Feasibility and climate pre-design1,500 – 4,000 €
Indoor pool enclosure design package8,000 – 25,000 €
Site supervision6 – 10 % of construction cost
Turnkey delivery2,000 – 4,500 € / m²

Frequently asked questions

What does an indoor pool cost to run?

The bulk of the cost is not the water but conditioning the room and dehumidifying it. A thermal cover plus a heat-recovery dehumidifier is what changes the bill.

Why is my pool hall ceiling condensing?

Because relative humidity exceeds the dew point of that surface. It is almost always insufficient dehumidification rather than insufficient heating.

Can an indoor pool be added to an existing house?

Yes, but it requires checking structure, clear height, plant room space and electrical capacity. That is the feasibility study we run before designing.

What are chloramines and why do they matter?

They are chlorine by-products that attack metals and airways. Good air renewal at water level keeps their concentration down.

Chlorine or salt electrolysis?

Salt reduces chemical handling but the atmosphere is still aggressive. The material specification does not change.

How long does it take?

Eight to fourteen months for new build or extension, depending on permits and structure.

An indoor pool is judged in its fifth winter, not in its first photograph.

Tell us the dimensions and the location and we start with the structural and climate study.