The Tarn Core, a tall stone column with a dial and grooves near its base, standing in a pale room in window light

A basin of stone.
A core that keeps it cold.

A cold plunge for the house, on a standard outlet, filled once with a garden hose.

Water 3.0 °C · held

Set once, held all year.

The Core keeps the Basin at three degrees through every season: no ice runs, no top-ups, no timers.

The rim of the stone Basin over still, dark water, with the window’s light reflected on the surface

3

°C

3

°C

3

°C

The Basin’s still teal water seen from above

You step in, you breathe, and three minutes later the day starts again.

You step in, you breathe, and three minutes later the day starts again.

One hand on the Basin’s stone rim, fingertips touching the water
One hand on the Basin’s stone rim, fingertips touching the water

Step in.

One hand on the rim, one step down, and sit.

One hand on the Basin’s stone rim, fingertips touching the water
One hand on the Basin’s stone rim, fingertips touching the water

Step in.

One hand on the rim, one step down, and sit.

Someone seated in the Basin, shoulders above the still water
Someone seated in the Basin, shoulders above the still water

Breathe.

Long, slow breaths out until the cold goes quiet.

A folded towel and wet footprints on the stone floor, the end of the Basin at the edge
Wet footprints on the stone floor beside the Basin and a folded towel

Step out.

A towel, wet feet on the stone, and the day again.

A folded towel and wet footprints on the stone floor, the end of the Basin at the edge
Wet footprints on the stone floor beside the Basin and a folded towel

Step out.

A towel, wet feet on the stone, and the day again.

The Basin’s still teal water seen from above

You step in, you breathe, and three minutes later the day starts again.

One hand on the Basin’s stone rim, fingertips touching the water

Step in.

One hand on the rim, one step down, and sit.

Someone seated in the Basin, shoulders above the still water

Breathe.

Long, slow breaths out until the cold goes quiet.

Wet footprints on the stone floor beside the Basin and a folded towel

Step out.

A towel, wet feet on the stone, and the day again.

The Basin and the Core in a room with a garden window, a folded towel on a wooden stool beside the Core

Made to live in a room.

The Basin and the Core in a room with a garden window, a folded towel on a wooden stool beside the Core

Made to live in a room.

The Basin is cut like furniture and sits where the light is. The Core stands on its own hose, wherever it fits, and keeps to itself.

Three materials, and nothing to hide: stone, copper and water.

A drop of water on the honed stone edge of the Basin

Stone

The Basin and the Core’s shell are honed cast stone, sealed against water, so water beads on its edge and never soaks in.

A drop of water on the honed stone edge of the Basin

Stone

The Basin and the Core’s shell are honed cast stone, sealed against water, so water beads on its edge and never soaks in.

The copper coil inside the Core, wound around a steel core

Copper

Inside the Core, a copper coil draws the heat out of the water, quietly, all day. You never see it; the dial on the face is all you touch.

The copper coil inside the Core, wound around a steel core

Copper

Inside the Core, a copper coil draws the heat out of the water, quietly, all day. You never see it; the dial on the face is all you touch.

The Basin’s teal water from above, window light across it and one ripple catching the light by the honed rim

Water

420 litres, filled once with a garden hose, filtered at 20 µm and turned over every day. It stays still and clear between plunges.

The Basin’s teal water from above, window light across it and one ripple catching the light by the honed rim

Water

420 litres, filled once with a garden hose, filtered at 20 µm and turned over every day. It stays still and clear between plunges.

Light ring

Status at a glance, on the cap.

One column does the cold.

The Core draws water from the Basin, chills it and sends it back, quietly, all day. Everything you touch is on its face.

One column does the cold.

The Core draws water from the Basin, chills it and sends it back, quietly, all day. Everything you touch is on its face.

Light ring

Status at a glance, on the cap.

One column does the cold.

Light ring

Status at a glance, on the cap.

The cold,

kept.

kept.

kept.

The Basin and the Core, measured.

Two parts, one hose between them, one outlet.

Point at a part
Point at a part

6 h

About six hours from 18 °C tap water to 3 °C.

6 h

About six hours from 18 °C tap water to 3 °C.

42 dB

At one metre, while the Core runs.

42 dB

At one metre, while the Core runs.

800 W

On one standard outlet, 120 V or 230 V.

800 W

On one standard outlet, 120 V or 230 V.

20 µm

Filtered; the whole Basin turns over every day.

20 µm

Filtered; the whole Basin turns over every day.

Basin

Outside

172 × 78 × 64 cm

Outside

172 × 78 × 64 cm

Outside

172 × 78 × 64 cm

Water

420 litres, 52 cm deep

Water

420 litres, 52 cm deep

Water

420 litres, 52 cm deep

Weight

180 kg empty

Weight

180 kg empty

Weight

180 kg empty

Material

Honed cast stone, sealed against water

Material

Honed cast stone, sealed against water

Material

Honed cast stone, sealed against water

Core

Size

26 × 26 × 96 cm, 36 kg

Size

26 × 26 × 96 cm, 36 kg

Size

26 × 26 × 96 cm, 36 kg

Cold

Holds 3 to 15 °C, set on the dial

Cold

Holds 3 to 15 °C, set on the dial

Cold

Holds 3 to 15 °C, set on the dial

Hose

3 m between the Core and the Basin

Hose

3 m between the Core and the Basin

Hose

3 m between the Core and the Basin

Warranty

Basin

5 years

Basin

5 years

Basin

5 years

Core

2 years

Core

2 years

Core

2 years

Cold, without the ice.

A plunge usually means a tub and bags of ice, or a drive to the spa. Tarn keeps the cold where you live.

Ready

Any hour, at home.

A tub and ice

Once the ice is in.

The spa

When it is open.

Ready

Any hour, at home.

A tub and ice

Once the ice is in.

The spa

When it is open.

Ready

Any hour, at home.

A tub and ice

Once the ice is in.

The spa

When it is open.

The cold

Yours to set, on the dial.

A tub and ice

Bags of ice, every plunge.

The spa

Whatever it is set to.

The cold

Yours to set, on the dial.

A tub and ice

Bags of ice, every plunge.

The spa

Whatever it is set to.

The cold

Yours to set, on the dial.

A tub and ice

Bags of ice, every plunge.

The spa

Whatever it is set to.

The water

Filtered and turned over every day.

A tub and ice

Changed by hand.

The spa

Shared.

The water

Filtered and turned over every day.

A tub and ice

Changed by hand.

The spa

Shared.

The water

Filtered and turned over every day.

A tub and ice

Changed by hand.

The spa

Shared.

In the room

A stone basin and one quiet column.

A tub and ice

A tub on the floor.

The spa

A drive away.

In the room

A stone basin and one quiet column.

A tub and ice

A tub on the floor.

The spa

A drive away.

In the room

A stone basin and one quiet column.

A tub and ice

A tub on the floor.

The spa

A drive away.

Ready in the dark.

Late or early, look for the blue ring on the Core’s cap. When it shows, the water is cold.

The Basin and the Core at night, the light ring on the Core lit blue

Questions, answered.

The top of the Tarn Core: the light ring around its cap, lit blue, and the dial on its face
The top of the Tarn Core: the light ring around its cap, lit blue, and the dial on its face
The top of the Tarn Core: the light ring around its cap, lit blue, and the dial on its face

The Core’s cap, and the dial that sets the cold.

No. The Core plugs into a standard outlet and the Basin is filled once with a garden hose. There is no plumbing to run.

Beside the Basin or around the corner. It is joined by one hose, so the room keeps one quiet object.

As cold as 3 °C. Set the dial anywhere from 3 to 15 °C and the Core keeps the water there.

The Core filters the water and turns it over every day, so the Basin stays still and clear between plunges.

We confirm your room, your delivery date and your price by email before anything is charged.

The Basin and the Core in a stone room, window light from the left, the water deep teal and still

Still water, ready when you are.

Reserve your Tarn

Nothing charged until you agree.

Reserve Basin and Core

The Basin and the Core in a stone room, window light from the left, the water deep teal and still

Still water, ready when you are.

Reserve your Tarn

Nothing charged until you agree.

Reserve Basin and Core

The Basin and the Core in a stone room, window light from the left, the water deep teal and still

Still water, ready when you are.

Reserve your Tarn

Nothing charged until you agree.

Reserve Basin and Core

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