Barrel Sauna 400 Thermo

Max-capacity barrel in durable Thermowood

Prices from

£9,495 inc VAT
STEP 1 OF 1

Choose your sauna timber

Choose your timber colour

Thermowood

Choose your roof shingles

Terracotta

Umber

Forest

Graphite

Onyx

Choose your sauna heater

Choose your back window

Choose your front window

Choose your add-ons

Product information

The longest standard barrel sauna, familiar build quality. Sauna 400 reaches a full 400cm while keeping the consistent 230cm diameter found across the smaller standard models. Solid Thermowood construction holds heat efficiently even with a larger group and frequent door use. Serious capacity without needing to weigh up an unfamiliar deluxe finish just for the extra length.

Heat Treated Thermowood

Heat Treated Thermowood

Built for Every Season

Built for Every Season

Everything You Need to Install

Everything You Need to Install

Designed for Fast Heat-Up

Designed for Fast Heat-Up

Specifications

  • Shape: Barrel
  • Accommodates: 7-8 People
  • Length: 400 cm
  • Diameter: 205/230 cm
  • Wall Thickness: Front 28mm / Sides 42mm
  • Material: Thermowood
  • Main Door: 160 x 59 cm
  • Window: 67 x 30 cm
  • Weight: 1050 kg
  • Package Size: 400 x 120 x 120 cm
  • Assembly: Self-assembly
  • Insulated: No
  • Design Note: Multi-room layout (changing area + sauna)

Designed around your ritual

Full Moon Back Window

Full Moon Back Window

Bring the outdoors in. A full circular rear window fills the sauna with natural light and opens up wider scenic views.
Half Moon Back Window

Half Moon Back Window

Privacy meets natural light. A half-moon rear window creates a softer, brighter feel while keeping more enclosed wall space.
Full Glass Front Barrel

Full Glass Front Barrel

Turn every session outward. Full front glazing opens the barrel sauna to natural light and uninterrupted outdoor views.
Full Glass Front Cube

Full Glass Front Cube

Modern design, open views. Full-height front glazing creates a brighter, cleaner space with a sharper architectural finish.
LED Lighting Kits

LED Lighting Kits

Set the perfect mood. Integrated LED lighting creates warmth and atmosphere, transforming the sauna experience day or night
Bluetooth Speakers

Bluetooth Speakers

Soundtrack your downtime. Built-in Bluetooth speakers bring music, podcasts, and guided sessions straight into your sauna.
Quality Accessories

Quality Accessories

Complete the experience properly. Practical finishing touches that improve comfort, convenience, and the overall sauna ritual.
Premium Thermowood

Premium Thermowood

Built to age beautifully. Thermowood offers a richer finish, stronger durability, and better long-term performance.
Genuine group capacity, without unnecessary finish upgrades, suits households whose priority is straightforwardly fitting more people comfortably rather than additional aesthetic features. The core physiological benefits of sauna bathing, improved circulation, reduced muscle tension, a cardiovascular effect comparable to light exercise, apply consistently regardless of finish level, and a sauna built specifically to maximise usable group space delivers genuine value for households focused on that priority.

The built-in changing area, even at this larger scale, continues to support a considered, unhurried ritual by keeping towels, robes, and general changing separate from the heat room itself. This matters as much, if not more, at this scale, since a busier sauna seeing regular group use benefits even further from that practical separation between functional and relaxing space.

For households who entertain regularly and have settled on genuine capacity as their main priority, the standard 400 offers a straightforward route to serious group sauna use without paying for deluxe detailing that wouldn't change how many people the structure can comfortably hold. That focus on practical capacity over additional finish tends to suit households who've already decided what matters most to them in a larger sauna purchase.
Delivered flat packed for self-assembly, with free UK mainland delivery on qualifying orders. As the longest standard barrel sauna, this build takes longer than the smaller sizes, best planned over several days with experienced help. Needs a solid, level base and good access. Professional installation is recommended; see our Self Assembly Guide.
The Sauna 400 needs the same fundamental barrel sauna care as the rest of the range, simply across considerably more surface area given its maximum length. After every session, leave the door open for twenty to thirty minutes to let the heat room dry out fully, preventing mould and dark staining on timber surfaces. Wipe benches down once cooled, and sand the interior lightly once or twice a year wherever group use creates the most contact wear.

The separate changing area should be checked periodically for dampness, ensuring it's drying out properly between sessions alongside the main heat room, particularly given the likely frequency of group use this size suggests. The window needs only a standard glass cleaner and soft cloth.

Externally, treat the curved Thermowood exterior with a wood treatment every two to three years, budgeting considerably more time for this longest structure in the range. Keep the full extended base clear of debris and standing water, checking drainage carefully given the greater length of timber in contact with the ground.
This sauna comes with a 5 year warranty for residential use and 2 years for commercial use, covering structural timber, glazing, and hardware. Valid claims are assessed case by case, and we'll supply replacement parts wherever possible rather than the whole sauna.
Production takes 10-12 weeks, plus 1-2 weeks dispatch time for pallet haulage. This sauna is delivered flat packed unless otherwise stated. Free UK mainland shipping applies to orders over £500 covering up to one double pallet (2.4m x 1.2m x 2.2m) or two single pallets (1.2m x 1.2m x 2.2m). Given this model's size and weight, additional pallet charges may apply and will be quoted separately based on your postcode, and forklift unloading may be required as it exceeds normal tail-lift limits (1000kg). Please have a solid base, clear access, and suitable unloading space ready before delivery, with help on site if needed. Pallet deliveries are kerbside only, and you're responsible for moving goods onto your property.
Health Benefits
Assembly & Installation
Delivered flat packed for self-assembly, with free UK mainland delivery on qualifying orders. As the longest standard barrel sauna, this build takes longer than the smaller sizes, best planned over several days with experienced help. Needs a solid, level base and good access. Professional installation is recommended; see our Self Assembly Guide.
Cleaning & Care
The Sauna 400 needs the same fundamental barrel sauna care as the rest of the range, simply across considerably more surface area given its maximum length. After every session, leave the door open for twenty to thirty minutes to let the heat room dry out fully, preventing mould and dark staining on timber surfaces. Wipe benches down once cooled, and sand the interior lightly once or twice a year wherever group use creates the most contact wear.

The separate changing area should be checked periodically for dampness, ensuring it's drying out properly between sessions alongside the main heat room, particularly given the likely frequency of group use this size suggests. The window needs only a standard glass cleaner and soft cloth.

Externally, treat the curved Thermowood exterior with a wood treatment every two to three years, budgeting considerably more time for this longest structure in the range. Keep the full extended base clear of debris and standing water, checking drainage carefully given the greater length of timber in contact with the ground.
Warranty
This sauna comes with a 5 year warranty for residential use and 2 years for commercial use, covering structural timber, glazing, and hardware. Valid claims are assessed case by case, and we'll supply replacement parts wherever possible rather than the whole sauna.
Delivery
Production takes 10-12 weeks, plus 1-2 weeks dispatch time for pallet haulage. This sauna is delivered flat packed unless otherwise stated. Free UK mainland shipping applies to orders over £500 covering up to one double pallet (2.4m x 1.2m x 2.2m) or two single pallets (1.2m x 1.2m x 2.2m). Given this model's size and weight, additional pallet charges may apply and will be quoted separately based on your postcode, and forklift unloading may be required as it exceeds normal tail-lift limits (1000kg). Please have a solid base, clear access, and suitable unloading space ready before delivery, with help on site if needed. Pallet deliveries are kerbside only, and you're responsible for moving goods onto your property.

Maximum length for serious groups

Sauna 400 extends the standard barrel format to 400 centimetres in length, the longest in the standard range while keeping the same familiar 230 centimetre diameter found across the smaller 220, 250, and 280 models. Solid Thermowood construction throughout gives the structure genuine thermal mass at this substantial scale, holding heat efficiently even with a larger group inside and more frequent door opening during a typical session.

At this length, Sauna 400 suits households who entertain regularly or simply want the largest standard barrel sauna available without moving into a deluxe finish or an entirely different format. The barrel shape continues to distribute heat evenly throughout the curved interior, an advantage that becomes increasingly valuable at this scale where a flatter walled structure might otherwise develop noticeably uneven temperature zones from one end to the other.

Sauna 400 suits anyone who has decided that a genuinely large barrel sauna suits their household best, delivering serious group capacity within the familiar, well proven standard specification rather than asking buyers to weigh up an unfamiliar deluxe finish purely to get the extra length they actually need. It remains the straightforward choice for anyone whose priority is space rather than additional finish upgrades.
Free Mainland UK Delivery Weather Resistant Thermowood Consistent Warmth Year Warranty Year-Round Use Heats Up Fast
Free Mainland UK Delivery Weather Resistant Thermowood Consistent Warmth Year Warranty Year-Round Use Heats Up Fast
Free Mainland UK Delivery Weather Resistant Thermowood Consistent Warmth Year Warranty Year-Round Use Heats Up Fast
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Maximum length, no unnecessary upgrades needed

Maximum length for serious group sessions, no unnecessary upgrades. The Sauna 400 prioritises genuine usable space for seven to eight people, with a built-in changing area included.

Built straightforwardly for genuine capacity

Built straightforwardly for capacity. This is the longest standard barrel sauna in the range, solid Thermowood construction throughout, designed for households who entertain regularly.

Real space for a group, kept practical

Real space for a proper group, kept practical. Separate changing area, maximum length, solid Thermowood construction, all focused on genuine group capacity rather than added finish.

For households whose priority is fitting everyone

For households whose priority is fitting everyone comfortably. The Sauna 400 delivers serious group capacity with a built-in changing area, straightforward and properly sized.

What our customers say

Don't just take our word for it

"The Cascina feels solid and well made. The aluminium frame has a clean finish, the roof panels sit neatly, and the whole structure gives the garden a much more complete look."

Aluminium Veranda | The Cascina | Modular Interlinkable | Multiple Roof & Post Styles

Olivia

The Cascina

"The Nobile has a really premium feel. The frame colour looks sharp, the materials feel durable, and the finished veranda has a clean modern appearance."

Aluminium Veranda | The Nobile | Wide Span Up To 7m | Extra-Large Gutter | Polycarbonate or Glass Roof

James

Nobile

"The Cascina suits the house perfectly. What stood out most was the sturdy frame, neat roof finish and how well the design works with the garden."

Aluminium Veranda | The Cascina | Modular Interlinkable | Multiple Roof & Post Styles

Charlotte

The Cascina

"The Fiano Glass Doors feel smooth, sturdy and well finished. They keep the space bright and open while adding extra comfort when the weather turns cooler."

Frameless Glass Sliding Doors | Fiano Glass Sliding Doors | 10mm Glass | Up To 7 Tracks | Veranda Garden Room Conversion

Henry

Fiano Glass Doors

Build your outdoor sauna

1

Choose the sauna size, layout and feel that suits your garden and routine.

2

Place your order and we confirm the key details before preparing your sauna.

3

Get ready for delivery, installation and proper heat sessions at home.

BUILD MY HOME SAUNA

Frequently Asked Questions

At 400 centimetres, it's the longest standard barrel sauna in the range, prioritising genuine group capacity over additional finish upgrades found on deluxe models.

Comfortably seven to eight people, making it one of the strongest options in the standard range for serious group sauna sessions.

A built-in changing area separate from the main heat room, keeping practicalities like towels and robes apart from the sauna itself even at this larger scale.

Yes, at 1050 kilograms it's a substantial structure, so proper delivery access and ground preparation should be carefully planned ahead of installation.

If genuine capacity matters more than an upgraded glazed finish, the standard 400 delivers the same maximum length without the additional cost of the deluxe specification.

5-Year Guarantee

5-Year Guarantee

Built for years of wellness and relaxation

Free UK Mainland Delivery

Free UK Mainland Delivery

Free delivery throughout England, Wales, and Scotland.

Expert Help, When You Need It

Expert Help, When You Need It

Friendly specialist support before and after your purchase. Schedule a virtual appointment.

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