If you're thinking of creating a wellness zone as part of your garden landscaping ideas, then including a sauna in your set-up is generally considered a must-have.
And while installing one outdoors is partially similar to putting one inside your home, there are certain differences that you need to bear in mind to ensure a safe and suitable construction.
The good news is, in some cases it's not as complicated as you might think. And with plenty of options from pre-fabricated to bespoke to choose from, these are the six mains things to consider if you're splashing out on a garden sauna.
1. You may need to arrange for groundworks
If you're adding a standalone or bespoke sauna to your garden, "the first thing to get right is the foundations," says Jake Newport, CEO of Finnmark Sauna. "In most cases, a sauna can sit on a solid concrete slab, paving base or properly built decking structure, so it’s a process that's much closer to foundations for garden rooms, than having to dig extension foundations.
"The important thing is that the base is level and well-drained," he explains, "so the structure stays stable over time and moisture doesn’t build up underneath.”
"Installing an outdoor sauna is generally very straightforward," adds Rasmus Tipp, marketing director at Iglucraft. "Most saunas simply require a stable, level base such as concrete pads, compacted gravel or a slab foundation, depending on the size and model."
Jake Newport is the CEO and founder of Finnmark Sauna, the UK’s leading specialists in authentic sauna design and installation. A leading voice in the industry, Jake is passionate about bringing authentic sauna experiences to UK homes through beautifully designed wellness spaces. He is also a council member of the British Sauna Society, member of Sauna from Finland and co-host of the Sauna Twins podcast, where he shares his expertise on sauna culture and innovation.
Rasmus Tipp, based in Estonia, is currently a Head of Group Marketing at Iglucraft. Rasmus Tipp brings experience from previous roles at Iglucraft.
2. Electrics, plumbing and ventilation will need to be considered
Your service requirements for an outdoor sauna will initially depend on the type of sauna heater you choose.
“With electric sauna heaters, you’ll need a dedicated electrical circuit installed by a qualified electrician because the heaters draw far more power than a normal household plug can handle," explains Jake Newport.
“But even with wood-fired saunas, some people still choose to run electrics for lighting, controls or additional features inside the sauna," he notes. That said, if you don't want to run electricity to your outdoor sauna, you could do without it if you opt for a wood-burning sauna stove."
“The main additional consideration with wood-fired saunas," advises Jake, "is the flue system. That needs to be installed properly with safe clearances around the chimney and surrounding materials.
“Plumbing for an outdoor sauna is usually much simpler than people expect because saunas themselves are dry-heat environments," he continues
“You don’t generally need permanent water lines or drainage for the sauna itself, which makes installation much more straightforward than a steam room or spa setup."
Instead, all you need is a fresh bucket of water to pour over the hot stones, but this could come from an outdoor tap located on your home's exterior walls, rather than inside the sauna itself.
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3. Planning permission and placement
Unless you're planning on including a larger-than-life wellness complex in your garden, most outdoor saunas should fall outside of planning permission requirements.
"In many cases, outdoor saunas fall within permitted development, meaning planning permission is not required," confirms Rasmus Tipp. "However, this can vary depending on the size, height and location of the sauna, as well as whether the property is listed or located within a conservation area. It is always recommended to check with your local authority before installation."
Regulations regarding proximity to boundaries and neighbours can vary between councils, "but generally outdoor saunas should be positioned with consideration for neighbouring properties and boundaries," notes Rasmus, "meaning factors such as overall height, proximity to fences and ventilation requirements may influence placement."
"There isn’t one fixed distance rule that applies in every situation, but spacing is important both practically and from a planning perspective," agrees Jake Newport.
“I also find that saunas tend to work best when they have a bit of breathing space around them," he adds. "If it’s pushed tightly into the corner of a garden, it can feel more like storage than somewhere you genuinely want to spend time.”
4. Can you put a sauna inside an outbuilding?
If you have an existing garden room (potentially with a bathroom) or outbuilding of any kind, you may be keen to expand its usability by installing a sauna inside it, but is this possible?
“Both work really well, and it often depends on how someone wants the overall space to function," says Erin Hickman, designer at Finnmark Sauna.
“A standalone sauna creates a very traditional experience because there’s that real connection with the outdoors. Stepping out into the cold air between sauna rounds is a huge part of what people enjoy about the sauna experience in the UK,” she expands.
"But, at the same time, we’re seeing far more people incorporate saunas into larger garden buildings or bespoke wellness spaces. That might be within a garden room or a more complete outdoor setup with changing areas, showers or cold therapy spaces alongside it.
“With bespoke outdoor saunas especially, there’s much more flexibility in how the sauna is designed around the space available," continues Erin. "We can adapt layouts, glazing, benching and proportions so the sauna feels fully integrated rather than something separate that’s been added afterwards.”
Erin Hickman is a sauna designer at Finnmark Sauna, with experience across residential and commercial architecture. With a Master of Architecture, she specialises in designing bespoke sauna spaces that are carefully considered around how people want to live and use their homes.
5. Maintenance and upkeep for garden saunas
Unlike indoor saunas, as outdoor saunas are exposed to the elements, there is naturally a bit more maintenance involved – as there would be with any outbuilding such as a garden room or even shed.
However, as is often the case, you get what you pay for, and investing in a quality product will make your investment longer-lasting.
"Built using carefully selected thermo-treated timber and traditional craftsmanship techniques, saunas from reputable companies are created to withstand changing climates while ageing beautifully over time," explains Rasmus Tipp.
"The unique three-layer timber construction of Iglucraft saunas for example is designed with air gaps and integrated insulation, to enhance thermal performance whilst creating a soft, organic texture that enriches the atmosphere inside."
Caring for the internal features of an outdoor wooden sauna is the same as an indoor one, and, again, looking after the timber and keeping the sauna properly ventilated makes a big difference over time.
“Externally, some people choose to treat the timber periodically to maintain the original colour," notes Jake Newport, "while others prefer to let it weather naturally.
“It’s also worth keeping the area around the sauna clear and checking for any signs of rodents or nesting creatures," he adds, "particularly around the base, ventilation gaps and any service entry points.”
And of course, the point of maintenance and upkeep of your outdoor sauna is the make sure it has longevity.
“A properly built sauna using durable timber and good ventilation and repeated weather-proofing should hold up extremely well outdoors for decades to come," advises Jake, "and like any outdoor structure, regular maintenance helps preserve both the appearance and performance of the sauna over time, particularly with exposure to changing weather conditions throughout the year.”
6. Cost for outdoor saunas
As an outdoor sauna is generally more sizeable and requires some structural work to install it, costs are of course more variable than an indoor cabin. But by how much?
"Our smaller barrel saunas start from around £3,300, which gives people a really authentic outdoor sauna experience without needing a huge amount of space," advises Jake Newport.
“From there, prices increase depending on the design, glazing, heater choice and how bespoke the setup becomes. Larger cabin saunas and more integrated wellness spaces tend to start from around £10,000.”
However, if you are looking for an authentic experience, the extra spend can be worth it he notes.
"A well-built sauna won’t just last better outdoors, it also changes the quality of the sauna experience itself. The quality of the heat comes down to details like insulation, airflow, timber choice and the heater itself. Those are the things that create the soft, even heat and proper löyly that Finnish saunas are known for."
Make sure you also factor in groundworks and any extension of services such as electrics when budgeting for an outdoor sauna, as it is these elements that may increase your budget unexpectedly if you haven't allowed for them upfront.
FAQs
What style of sauna should I choose for my garden?
“Choosing an outdoor sauna comes down to two things," says Erin Hickman. "How you want to use the sauna, and how it sits within the garden itself.
“For gardens with softer planting and a more natural feel, such as cottage gardens, barrel saunas work beautifully because the curved shape sits very comfortably within greenery and feels rooted in traditional Nordic sauna culture.
“In smaller or more modern gardens, cube saunas tend to work really well because the cleaner lines feel more aligned with modern landscaping," she suggests. They work particularly well in more compact gardens or contemporary outdoor spaces.
“For those wanting something more architectural in feel, cabin saunas give you much more flexibility with glazing, proportions and internal layout," continues Erin. "They also allow for more spacious layouts and longer social sauna sessions.
“Each style offers something slightly different, so it’s less about one being better than another and more about finding the sauna that feels most natural within the space and how someone wants to use it.”
What outdoor sauna designs are popular?
“Outdoors, barrel saunas remain especially popular because they’re the style many people first experience at public saunas and they have a strong connection to more traditional sauna culture," says Erin Hickman. "As sauna and cold water wellness becomes more mainstream in the UK, people are increasingly looking to recreate some of that experience at home.
“We’re also seeing more interest in creating wider wellness spaces around the sauna itself, whether that’s adding cold plunges, outdoor showers or simple areas to slow down and relax afterwards.”
Could I put an outdoor sauna inside my garage?
"Garages or garage conversions can work very well for indoor saunas, especially if they’re properly insulated and ventilated," confirms Erin Hickman.
“A lot of people like using garages because they offer more flexibility with layout, and usually make it easier to install the required electrics. They can also create a slightly more separate, retreat-like feeling away from the main part of the house," she adds.
“However, the key consideration is making sure the environment will be able to handle the moisture.”
With such a wide variety of sauna designs available, it makes them suitable for all different styles of garden. So whether you're looking at creating a secret wellness space in the corner of a garden, or including a hot tub and sauna on your patio, there's no reason why you can't put wellbeing at the centre of your garden design.
