Redwood Outdoors Thermowood Garden Sauna Review

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Key Features:

• Constructed with interlocking Scandinavian Thermowood staves which allows the wood to expand and contract ensuring a tight seal
• Seats up to eight individuals dependant on each person’s size and seating arrangement
• Two-level stadium benches
• Designed with heat-treated Scandinavian softwood using steam and protective gas
• Environmentally friendly with wood sourced from PEFC-certified forests, an international third-party certification for sustainable forest management
• Operates using Harvia heaters, all of which are ETL certified, ensuring they meet industry standards through testing by an international accrediting association
• Thermostats may be controlled manually or with Wi-Fi via a digital wall pad mount or smart device

Sauna usage has been a longstanding tradition in Finland for thousands of years, offering relaxation, wellness and an enjoyable pastime to its inhabitants. Beyond its cultural significance and historical roots, sauna bathing has been linked to multiple health benefits. Studies have indicated that it can help to alleviate pain and symptoms related to musculoskeletal disorders while also reducing the risk of cardiovascular diseases. In fact, emerging research suggests that sauna bathing may even lower the risk of high blood pressure, neurocognitive diseases and mental health disorders.

When combined with regular exercise, the potential benefits of sauna bathing keep increasing. Research has demonstrated that it helps to alleviate inflammation, provide relief from chronic pain, reduce joint stiffness and ease muscle tension. Not to mention that saunas are also a great recovery tool for both athletes and everyday gym goers. But, in our busy lives, finding time to go to your local gym or spa can be challenging. This begs the question: why not bring the sauna experience home with your very own spacious outdoor sauna?

Modern saunas go beyond traditional saunas and the old school wooden box found in the corner of a gym somewhere. At-home saunas now come in various sizes, models, types and price ranges, catering to diverse preferences and needs. You can find outdoor barrel saunas, cube saunas, saunas that fit into a corner and more. Although there are saunas available at an array of price points, it's important to recognize any sauna you choose will likely be a financial investment.

If you are on the market for a sauna and considering Redwood Outdoors’ Thermowood Garden Sauna, you have come to the right place. In our comprehensive review, we will explore everything you need to know about this sauna including specs, features, functions, available upgrades and a glimpse into genuine customer experiences. Because, afterall, investing in a sauna is a decision you want to make with certainty. So are you ready to dive in and discover if this sauna is the one for you? Here we go.

Spec Overview

• Seating capacity: Six to eight people dependent on the size and proximity of bathers
• Wood tye: Scandinavian Thermowood
• Exterior dimensions: Roof - 105.5 inches L x 90.5 inches W x 99.25 inches H; base - 102.75 inches L x 89 inches W
• Shipping dimensions: 94 inches L x 43.5 inches W x 37.5 inches H
• Weight: 1,500 pounds
• Door: Wooden door with glass window
• Electrical requirements: 110 volts for lighting, 240 volts for heater

Pros of the Thermowood Garden Sauna

• Designed with high-quality Scandinavian thermowood
• Engineered with non-toxic, eco-friendly material
• Both manual and remote control options for temperature and time
• Spacious enough to lay back comfortably
• Visually appealing
• Good seating capacity (up to eight)
• Window on the entry door and full glass doors so you can peak out (a great perk if you live somewhere with a view)

Cons of the Thermowood Garden Sauna

• Plan to dedicate a good chunk of time for on-site assembly as it is reported, by Redwood and user reviews, to be complex
• It’s geared for the DIY individual with a decent woodworking skill set so not a great option for everyone
• Weight – it is heavy and you will need the help of some friends to get all the pieces moved and assembled
• You can’t upgrade to a Wi-Fi heater at a later time so you have to decide if you want that feature before placing your order

Who the Thermowood Garden Sauna is Best For

• People with large yards or enough real estate to place the sauna unobtrusively
• Someone who has good woodworking skills and enjoys DIY projects
• Those who plan to use this with multiple people as it really is not designed as a personal sauna
• Anyone who appreciates a beautiful and functional design

Construction and Design

Redwood put a premium on both design and performance with the Thermowood Garden Sauna striving to emulate a true Finnish sauna experience. We are going to explore this sauna’s design and engineering which is where the Garden Sauna really shines.

Technology and stand-out features

Perhaps the biggest stand-out feature of this multiple person sauna is its top-of-the-line engineering and material. The Garden Sauna is constructed with heat-treated Scandinavian thermowood. The process entails placing the wood in a low oxygen chamber kiln where it is exposed to temperatures that range from 180-degrees to 230-degrees for up to 96 hours using water and steam only. The steam in this chamber creates a protective gas that is stated to prevent damage to the wood.

This process is claimed to bring about chemical alterations in the cell wall structure, including the breakdown of hydrophilic hemicelluloses and the formation of chemical bonds through lignin cross linking making it a much better choice than untreated wood. Additionally, the crystal structure of cellulose may undergo modifications. Now, those are a whole lot of big and scientific words which mean very little to the average person (I am pointing at myself here). So what does it really mean? Here is what you need to know and why it is important for us to call-out.

The changes in the wood's chemical composition from this process is said to have a direct impact on its physical and mechanical characteristics. Specifically, it improves the dimensional stability of the wood helping it to maintain its shape under high temperatures, a feature that is especially important in the material used for saunas. Heat-treated wood also is more resistant to fungi, rot and damage while boasting improved insulating properties.

The Garden Sauna also uses an interlocking system for the actual assembly of the wood. Not only does that make a visually attractive design but it also allows for the natural expansion and contraction creating a tight seal. The outcome is a carefully crafted sauna designed to withstand repeated use, ensuring its durability.

All of Redwood’s saunas use Harvia sauna heaters which, according to Redwood, is a company that designs reliable and high-quality heaters. All Harvia sauna heaters used in Redwood’s products are ETL certified which means they have been tested and found to be in compliance with published industry standards. Made from stainless steel, the heater is then coated with a red enamel.

Redwood offers two control options on heaters for the Garden Sauna: a manual control or Wi-Fi. The manually controlled sauna heaters feature two dials, one of which controls the temperature and the other works as a timer. This adds a nice convenience factor as the timer has up to an eight-hour delay which means you can set it early and have it ready for use when you want at a later time.

If you prefer a Wi-Fi controlled heater, you need to make that decision upfront. Redwood explains that because the two heaters function so differently, you can not upgrade at a later point. The Wi-Fi heater certainly has the technological edge and makes it really easy to control your sauna from anywhere. There is a mounted digital wall pad which you can use or remote start using your smart device. Wi-Fi heaters can also be set to turn on at a certain time of the day so you can set it and forget it.

Upgrades

Redwood offers several upgrades to the Garden Sauna. While not all of them are absolutely necessary, there is one that both our team and Redwood Outdoors strongly encourage you to consider–roof shingles. These asphalt black shingles are a way to protect the wood on the roof from the elements. In doing so, you are extending the wood’s lifespan. For $199.00, this add-on really is one you may want to purchase. While the Garden Sauna is not the most expensive sauna on the market, it still is an investment so it is a good idea to protect it.

Depending on your budget, the deluxe accessory kit is a cool upgrade to tack onto your order. This all-in-one kit includes a wooden bucket, ladle, thermometer and timer. With this, you can toss some water on the hot rocks, relax and take in the steam. The thermometer allows you to monitor both the temperature and humidity while tracking your session time with the timer. This kit sells for $99.00. It is not something you need but does bring the sauna experience up a notch.

If you really want to be fancy, you can add-on a lie-flat wooden recliner for $279.00. The backrest is adjustable so it’s designed to accommodate people of different sizes. Personally, I think the recliner is a really nice option. Whenever I've been in a sauna, I always feel incredibly relaxed and have the urge to lie back and unwind. However, the flat benches in saunas are not usually the most comfortable for reclining. So if you can afford it, consider this add-on. I know I would!

Redwood also suggests their deluxe outdoor shower as an upgrade for the Garden Sauna. It boasts a classic barrel shape to ensure privacy. If you are not sure about this one, you can always purchase it at a later time. It is listed for $999.00 whether you add it to this order or buy it on its own (though you would need to pay for shipping).

If you're interested in trying out the widely popular "Fire and Ice" technique for recovery, Redwood recommends purchasing the Alaskan Cold Plunge Tub with the Garden Sauna. “Fire and Ice” really just means incorporating both heat and cold immersions (aka cold plunge tubs) into your fitness routine to enhance recovery. Recent research suggests that applying heat and cold post-exercise can have beneficial effects on training and accelerate the recovery process. In fact, the American Council of Education (ACE), a highly respected accrediting body for fitness professionals, encourages personal trainers to integrate this technique into their clients' wellness regimen.

Related Post: Redwood Outdoors Cold Plunge Review

Adding on the Alaskan Cold Plunge Tub offers the cold therapy you may be looking for to balance out your recovery routine. This tub is delivered fully assembled, featuring a plastic liner on the inside and spruce thermowood covering the exterior. It also includes a pre-installed bench. To use this tub, simply fill it with cold water and ease yourself in. Selling for $1,999.00, it is an expensive add-on. But, it would be pretty cool to transform your backyard into your very own spa oasis!

Check out our Redwood Outdoors Pacific Cold Plunge Kit review for more information about this brand's popular cold plunge tub!

Using the Thermowood Garden Sauna

Setup and assembly

I am going to get this out there – the setup and assembly of the Garden Sauna is no walk in the park. The glass front door window, stadium seating, glass doors and intricate overall design add some complexity making it more challenging to put together than the Therawood barrel saunas or other smaller saunas. Redwood advises that assembling the garden sauna demands a solid level of DIY and woodworking skills. While there is no specific timeframe provided for the setup, it is noted that the build time is longer. It would be wise to enlist the assistance of friends who are experienced and confident in tackling DIY projects.

The Garden Sauna is shipped in a wooden crate which measures 94 inches long, 43.5 inches wide and 37.5 inches high. According to customer support, the crate is delivered to the edge of your driveway. Let’s not forget that this bad boy weighs 1,500 pounds so moving the crate in one fell swoop is not an option. Instead, customer service told me that users have to pop off the top of the crate and physically move each piece of wood to where you plan to place the sauna. Not the most time-efficient process but way more feasible than trying to figure out a way to move it as a whole.

Before you even get started with the on-site assembly process, you need to ensure that your ground has a strong and level foundation capable of supporting the weight of the sauna plus occupants. While the sauna assembly itself does not necessitate professional assistance, it is important to note that the heater installation must be performed by a registered electrician for proper wiring and safety.

Redwood provides a comprehensive video on their website that guides you through every step of the assembly process. You can easily follow along as someone demonstrates the entire assembly from start to finish. You also have the option to receive a copy of the assembly instructions via email. However, it's worth noting that when I tried to snag a copy for myself, I was required to confirm a subscription to Redwood (aka marketing emails galore) and schedule an appointment with a product specialist. I never actually received the manual as expected. That said, the product specialist was extremely helpful.

Once your sauna is installed, using it is quite simple. Just adjust the temperature and time using the control system you have, wait for it to heat up and you're ready to enjoy. Numerous users have mentioned that the heaters perform exceptionally well and the sauna reaches the desired temperature rapidly. So really, it couldn't be much easier to operate.

Related Post: The Best Portable Saunas

Ordering and delivery

When purchasing your new Garden Sauna, you have the choice between four different heaters: 9 kilowatt HUUM Drop Electric Heater, 9 kilowatt Harvia Cilindro Electric Heater, 8 kilowatt Harvia Kip Electric Heater or Harvia M3 Wood Stove. Here is what you need to know about each one.

The HUUM Drop Electric Heater has a modern, water-drop shaped design. It holds up to 120 pounds of sauna rocks and reportedly emits a balanced amount of steam reaching temperatures up to 195 degrees Fahrenheit relatively fast. Every HUUM DROP is delivered with sauna stones and a HUUM UKU Wi-Fi controller which makes it especially attractive to those who prefer modern functionality.

If you are looking for a wall-mounted heater, the Harvia Kip Electric Heater is the one for you. With a capacity to hold 40 pounds of sauna rocks, it can reach temperatures up to 190 degrees Fahrenheit in one hour or less. This heater offers a dryer heat with a lower relative humidity of approximately 15 to 25 percent. Featuring a stainless steel exterior case, the Kip is available with Wi-Fi or manual controls.

The Harvia Cilindro Electric Heater is recognized by Redwood for producing a substantial amount of steam creating a hot, steamy and humid environment. It can hold 160 pounds of rocks which is reported to allow for an even distribution of heat. This heater takes slightly longer to heat up and operates at a slightly lower absolute temperature of around 165 degrees Fahrenheit. As with some of the other electric heaters, the Cilindro can come with a Wi-Fi control system or manual.

There is only one option for a wood-burning stove, the Harvia M3 Wood Stove which offers a more classic sauna experience. This compact wood fired stove creates a warm steam and is larger than the other options. As a result, the seating capacity is reduced. The M3 does not come with a chimney kit so be prepared to purchase eight feet of six inch double-wall stove pipe, interior protective flashing, a chimney collar and an external rain flange. Installing it will require you to cut a hole in the roof staves and is essential for proper functioning.

Electricity requirements

The Redwood Garden Sauna needs 110 volts for lighting. The sauna does come with an overhead light which, again, means you need an electrician for installation. Heaters require 240 volts so just ensure you have the capacity to meet these requirements in the area you want to keep it.

Customer Reviews

The customer feedback for the Garden Sauna is overwhelmingly positive. While there are only a few reviews specifically for this sauna model, many customers express their satisfaction with the overall experience of dealing with the company. The reviews that are available are sourced exclusively from the Redwood website, so I would not expect to see anything too negative.

One customer referred to the Garden Sauna as the “coolest project ever,” going on to state “the wood was perfectly milled. There were no alignment problems. The figures were understandable and EVERYTHING was included. The guys at Redwood Outdoors even asked when I was assembling so they could be available if I needed to call. WOW, after using the Garden Sauna for 5 weeks I can’t say how cool it is.”

Another reviewer writes “man I am thrilled with how this sauna performs and how it looks in my yard.” One other customer states, “I have had this sauna for two years now. Craftsmanship is still solid and the sauna is still very much enjoyable.ra”

There are multiple reviews raving about the customer service with high recommendations for the company as a whole. One user writes, “Redwood Outdoors has super customer service. They were all very responsive and friendly.” Another goes as far as saying that going with Redwood Outdoors is the “best life changing decision you’ll ever make,” claiming that “Redwood Outdoors cares about making customers happy and will do whatever it takes to make things right.”

Final Verdict

The Thermowood Garden Sauna by Redwood Outdoors is a high-quality, spacious outdoor sauna. Constructed with heat-treated Scandinavian thermowood and featuring an interlocking system, this sauna is durable and visually appealing. You can customize your sauna experience by choosing between four different heater options, some of which can be controlled manually or through Wi-Fi, providing convenience and flexibility. The sauna offers seating for six to eight people, making it a good choice for larger groups. While assembly can be complex and time-consuming, the sauna's performance and quick heating capabilities receive overwhelmingly positive reviews.

FAQs

How hot does the Thermowood Garden Sauna get?

Depending on which heater you purchase, the Thermowood Garden Sauna can reach temperatures as high as 195 degrees with the HUUM DROP, 190 degrees with the Harvia Kip and 165 with the Harvia Cilindro.

How many people does the Thermowood Garden Sauna fit?

The Thermowood Garden Sauna fits six to eight people depending on individual size and seating arrangement.

Should I add any of the upgrades to the Thermowood Garden Sauna?

Most of the upgrades are really a matter of personal preference and budget. However, we would encourage you to strongly consider adding the asphalt black shingles to protect your new investment. The sauna kit is a nice upgrade and will enhance your experience but certainly is not a necessity.

Is the Thermowood Garden Sauna steam or infrared?

The Thermowood Garden Sauna is steam based.

Does the Thermowood Garden Sauna have a warranty?

Yes, the Thermowood Garden Sauna comes with a one-year limited warranty. You can find the full description of the warranty on their website for further details.

What do I do if I need a replacement?

If you need a replacement part simply reach out to Redwood. They claim to keep replacements of nearly all parts on hand and can get them shipped to you quickly. 

How do I get the best sauna experience?

Redwood offers some information on the best sauna experience. They recommend beginning by preheating your sauna to your desired temperature, typically ranging between 160-185°F. While the sauna is warming up, take the opportunity to hop in a warm shower or hot tub. Once the sauna has reached the desired temperature, enter the pre-heated sauna and allow your body to relax and sweat it out. It is important to note that during the initial phase of the session, it is recommended not to throw water on the rocks.

After spending some time in the sauna, Redwood recommends cooling off by taking a cold shower or doing an ice bath. Once you have cooled down, re-enter the sauna and sprinkle water on the rocks. This will increase the humidity to approximately 30%, aiding in perspiration. It is advised to use about half a cup of water every 5 minutes during your sauna session, as using too much water can cool down the rocks and result in less steam.

What kind of foundation do I need?

According to Redwood, it's crucial to choose a site with a strong foundation. Given that the sauna can weigh over 1000 lbs when occupied, options like a deck (if very sturdy) or concrete pad may work well. If placing the sauna directly on the ground, Redwood recommends using concrete pavers under the support cradles to prevent settling and maintain a level surface over time.

Prices are accurate and items in stock as of publish time.