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SaunaLife Model S4B Wood-Fired Hot Tub

Name: SaunaLife Model S4B Wood-Fired Hot Tub
Brand: SaunaLife
SKU: SL-MODELS4B
Price: 5990.00 USD
Availability: InStock

By: SaunaLife

Type: Hot Tubs

SKU: SL-MODELS4B

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$5,990.00

$5,990.00 ~~$7,986.67~~

$950 Shipping to USA

Curbside Delivery

Is a sauna heater included with the sauna?

No, the sauna heater is not included and is sold separately. It is offered as a separate selectable option, as this approach gives you the flexibility to choose a heater that best suits your needs and budget. Our team has carefully selected compatible heater options specifically designed for this sauna. To explore and choose a heater, simply click “Add a Sauna Heater” to view the available options.

How will my order be delivered?

Your sauna will be delivered on a large pallet through LTL freight, with the driver placing it at the curb (curbside delivery). From there, you can carry the individual panels to your installation area, as most pieces can be carried by two people. You'll receive tracking updates throughout the shipment, along with a call in advance to arrange a suitable delivery time. In some cases, the driver may place the kit in a nearby garage at their discretion. Our team is dedicated to making sure your sauna arrives smoothly, on time, and without inconvenience.

Is the sauna delivered pre-assembled?

This sauna is shipped as a DIY kit. Most models can be assembled by two people in under a day, while larger units may require additional time. All kits come with detailed instructions for easy setup. For additional information on assembly, installation requirements, and estimated timelines, please see the product specifications below.

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Features

SaunaLife Model S4B Wood-Fired Hot Tub

Thermo-Spruce materials (lasts up to 2X longer than Cedar)
Luxury outdoor wood-burning hot tub
Designed for outdoor ergonomic hot tub bathing experiences
Arrives fully assembled and no electricity required (eco-friendly)
Spacious interior holds over 304 gallons of pure water bathing pleasure
Thick dark grey contoured fiberglass lining provides enhanced bather comfort
Stainless steel wood-burning heater utilizes dual heat compartments for unmatched efficiency
Rapid response heat-up time prepares water to ideal temperatures in under 2-hours
Wood-burning heater constructed of 304 stainless steel
Polished stainless steel chimney with protection
Durable Thermo-Spruce tub surround (1.65” thick), painted black
Superior thermal resistance (R-value) to retain heat
Matching Thermo-Spruce wood steps for easy access
Extra thick steel reinforced foam cover, folds for ease of removal and storage
Dark grey marine grade vinyl cover exterior
Integrated hot tub drainage tap
Up to 6 bathers
Exterior dimensions – 79" diameter and 37” high
Interior dimensions – 71" diameter and 33” deep
Designed by SaunaLife and handcrafted in Northern Europe

Thermo-Spruce Material Advantages

Lasts up to 2X longer than Cedar
Superior thermal resistance (R-value)
Eco-friendly
Ideal for water use (stable)

Specifications

SaunaLife Model S4B Specifications
Model	S4B
Construction
Material	Thermo-Spruce
Dimensions
Interior Dimensions	71" Diameter × 33" D
Exterior Dimensions	79" Diameter × 37" H
Water Capacity	304 Gallons
Product Weight (Filled)	3064 lbs
Heating System
Stove Dimensions	19.8" L × 11.8" W × 13.1" H
Chimney Dimensions	95" H × 4.7" Diameter
Maximum Wood Length	16"
Maximum Temperature	106°F
Shipping Details
Shipping Dimensions	91" L × 46" W × 87" H
Shipping Weight	595 lbs

Includes

SaunaLife Model S4B Wood-Fired Hot Tub

Fully assembled hot tub
Steps
Insulated cover
Drainage with tap
Polished stainless steel chimney
Chimney cap

Manual

SaunaLife Model S4B Wood-Fired Hot Tub

Description

SaunaLife Model S4B Wood-Fired Hot Tub

The SaunaLife SOAK-Series Model S4B represents the very best in wood-burning hot tub quality, efficiency, and luxury.

Thermo-Spruce materials (lasts up to 2X longer than Cedar)
Luxury outdoor wood-burning hot tub
Designed for outdoor ergonomic hot tub bathing experiences
Arrives fully assembled and no electricity required (eco-friendly)
Spacious interior holds over 304 gallons of pure water bathing pleasure
Thick dark grey contoured fiberglass lining provides enhanced bather comfort
Stainless steel wood-burning heater utilizes dual heat compartments for unmatched efficiency
Rapid response heat-up time prepares water to ideal temperatures in under 2-hours
Wood-burning heater constructed of 304 stainless steel
Polished stainless steel chimney with protection

Model S4B Outdoor Wood-Burning Hot Tub

The SaunaLife SOAK-Series Model S4 represents the very best in wood-burning hot tub quality, efficiency, and luxury.

Ready for your hot tub party

The Model S4B wood-fired hot tub arrives completely assembled and is easy to set up. Its ergonomically shaped fiberglass tub is a comfortable place for up to 6 people. The interior surface is easy to clean, and the exterior is crafted from thermally enhanced spruce for superior weather resistance and durability.

Engineered for efficiency and performance

Engineered and crafted in the Northers Europe, this super-efficient hot tub heats in 1/3 of the time as traditional wood-fired hot tubs. No electrical connection is required. At the heart of the Model S4 is its ingenious self-cleaning corrugated stove with a secondary chamber that transfers heat from the smoke – reducing wood consumption up to 50% compared with other hot tubs. Brilliantly, the air between the fiberglass lining and the wood exterior is super-heated to accelerate the heating process. The stove is cleverly engineered to draw cooler water through a lower channel and redistribute it though an upper channel to equalize the temperature.

Start enjoying sooner

This incredibly efficient wood stove will heat 304 gallons of water from 40°F (5°C) to 95°F (35°C) in 1.5 to 2 hours – the fastest-heating wood-burning hot tub available.

Relax with friends and family the luxury of your Model S4 backyard wood-burning hot tub from SaunaLife.

Shipping & Returns

When will I know my order has shipped?

Once you place your order, you’ll receive a confirmation email. This means we’ve received your order and pre-authorized your card. After confirming availability, we process the payment and shipments typically leave the warehouse within 3 business days. If an item goes out of stock, we’ll notify you immediately and work with you on the next steps.

What if my shipment is damaged?

Inspect the packaging when it arrives. If you see any damage, note it when signing for delivery. If your item arrives damaged, please email photos of the damage along with your order number to . Our team will review the issue and guide you through the next steps.

Refunds & Returns

Exchanges are available. The customer is responsible for shipping costs on all returns and exchanges. Not every order can be returned once shipped. We source directly from manufacturers, and when a manufacturer doesn’t allow returns, we can’t offer one either. This varies by brand and product, so contact us for specifics on your item.

Due to rising LTL/freight costs, outright returns are subject to a 25% cancellation fee plus return shipping. If you’re exchanging for another product, we may be able to help offset some of the cost depending on the item.

We reserve the right to withhold any refund or cancel any payment owed until we (a) receive the goods, (b) inspect them, and (c) determine at our discretion that they are free of damage. Refunds are issued within 5 business days 5 business days once the product has been returned to the warehouse and inspected for damage.

Customers praised this wood-fired hot tub for excellent heating performance and solid build quality. "Heats up in under 2 hours" and "burns way less wood than expected." The fiberglass finish is comfortable and easy to clean. Comes fully assembled for easy setup. Note: unit is larger than expected, so careful space planning is recommended.

Heats up in under 2 hours consistently which still surprises me.
Burns way less wood then expected, the dual chamber makes a real difference.
Once installed it heats consistently and the build quality is solid.

5 stars: 8 (89%)
4 stars: 1 (11%)
3 stars: 0 (0%)
2 stars: 0 (0%)
1 star: 0 (0%)

Some of the reviews shown are from related products the merchant grouped with this one.

Beautiful natural wood hot tub

We went with the S6N in the natural Thermo-Spruce finish and it looks great on our property, blends right in with the surroundings. The wood fired stove is really efficient, burns way less wood then we expected compared to our old tub. The corrugated stove design is clever, basically cleans itself which is a nice bonus. Water heats up evenly throughout, no cold spots which we had issues with before. Fiberglass interior is comfortable, we've done some long soaks and no complaints. Delivery came fully assembled which made setup way easier then we anticipated. Overall the quality is just really solid, you can tell its well made. Very happy with it.

Essential recovery tool

Got the S2N in natural wood and it looks really good in our backyard, fits the space better then a regular cold plunge would. We use it after workouts, my partner and I both fit no problem. Thermo-Spruce holds up better then cedar from what we've read and so far that checks out, been out in the elements and looks the same as day one. Easy to keep clean, no real maintenance to speak of. If you work out regularly and want something that actually helps with recovery this is a solid option.

Great solo cold therapy tub

S1N fits perfectly on my back patio, doesnt take up much space at all. Easy to clean, looks great in natural wood. Morning plunges have become a non negotiable for me. Solid build, no complaints.

Good heater needs space planning

This SaunaLife works well but is larger than I anticipated. Make sure to measure your space carefully. Once installed it heats consistently and the build quality is solid. Performance is excellent.

Best wood hot tub available

S4B looks really sharp in black, gets a lot of comments from guests. Heats up in under 2 hours consistently which still surprises me. Burns way less wood then expected, the dual chamber makes a real difference. Came fully assembled so setup was easy. Fiberglass is comfortable and wipes down fast. Really solid tub overall.

Perfect 2-person cold plunge

We picked up the S2B to pair with our sauna for contrast therapy and its been worth every penny. Use it daily, basically part of our routine now. The black finish looks really clean, holds up well outside too. Thermo-Spruce is solid, no issues with the build at all. Fits two people fine for what we use it for. Fiberglass interior wipes down easy, no maintenance headaches. Honestly didnt expect to love it as much as we do but its become just as important as the sauna itself for recovery.

Amazing 7-person hot tub

We got the S6B for our cabin and honestly its been perfect for get togethers. Fits 7 adults no problem, actually has room to move around which I didnt expect. The black Thermo-Spruce exterior looks really sharp, holds up well outdoors too. Water heats up faster then I thought it would, under 2 hours which for a wood fired tub is pretty impressive. Doesnt burn through wood as fast as our old setup either, the dual chamber design makes a real difference. No electricity needed which was the whole point for us, we're fully off grid up there. Fiberglass interior is easy to wipe down after. We've had a few hot tubs over the years and this one is the best we've owned by a good margin.

Compact cold plunge perfection

Got the S1B for daily ice baths and its exactly what I needed. Black finish looks clean, depth is spot on for full immersion. Been outside through some rough weather and holding up great. Recovery has been noticeably better since I started using it consistently. Really happy with this thing.

Efficient wood-fired hot tub

We've had a few wood fired tubs over the years and this one heats up faster then any of them. Fits 6 people comfortably, good size for the price. Natural Thermo-Spruce looks great on our property, very organic feel. No electricity needed which was a must for us off grid. Stove is efficient, doesnt burn through wood like you'd expect. Really well made overall.

SaunaLife Model S4B Wood-Fired Hot Tub