My friend Simon lives in north Wales and has been building and using saunas regularly for 10 years. Recently he invited me to help him build a new one. He is something of a connoisseur: this was to be his third — one is connected to his bathroom, the other one is in a 300-year-old pigsty and this new one will be built into a steep hill, with a view.
Why does he need so many saunas? His partner tells me people in the village have asked the same question. Simon laughs. It’s become a hobby, like collecting cars, I guess.
From my experience as a carpenter, saunas can be some of the most challenging and interesting structures to build. The wood must be high quality and able to withstand extreme temperatures, swelling and shrinking as the sauna is heated and exposed to steam. And, given the rich tradition of sauna design around the world, at the highest level they should be a display of precise and skilled craftsmanship.
But there is also the experience: the dark, silent spaces and the elusive, contented clarity — a washed-out, clean feeling in the mind — that follow a proper sauna session. Mine is a fascination — and enjoyment — that is shared with many people around the world.
Honouring and progressing this architectural tradition is the €6mn public sauna in Helsinki. Named “Löyly”, Finnish for “steam”, and opened in 2016, it was designed by architects Anu Puustinen and Ville Hara of Avanto. “In an increasingly secular Finland, the sauna has become like a kind of holy space, to gather with community, and to cleanse one’s body, mind and spirit,” says Puustinen. He adds that the Löyly sauna had earned all its funding back within three years.
To build a sauna is to create a warm pocket of life, rich with aromas of wood, that connects people and builds community. Emma O’Kelly travelled much of the sauna-going world for her book Sauna: The Power of Deep Heat, published in September, meeting hundreds of people of all ages, genders and backgrounds.
“They all talked about how good a sauna makes them feel — it’s a space where no one is judged and people can be free to sit in silence, or go and talk with friends,” says O’Kelly. “It is almost like a sacred space, as it was in the olden days: babies were born in the steam, the dead were prepared for burial and all life’s rites of passage were celebrated.”
My friend Simon says they are “somewhere between a chapel and a pub”.
His build was traditional; a model of perfect simplicity in sauna design. And probably one that — with basic DIY skills — most people could follow to make a high-quality sauna in a few weeks. Built of dense larch, with a pitched roof, a large wood-burning stove and a small, thin window, this sauna will look out from its perch across lush green valleys and sheep-dotted hills.
“Saunas can be really straightforward when you keep the materials simple,” says Lewis Jenkinson, technical officer for the British Sauna Society. “Just build the structure out of thick timber; wood breathes, it has thermal mass, its own insulation, and all the properties of a more complicated stick frame cabin.”
The majority of the build at Simon’s house took us one week. First, we built foundations from large pieces of slate salvaged from a crumbling dry stone wall. We stacked the slate roughly knee high in the shape of the sauna, and filled the gaps in the slabs of slate with mortar; a standard mix of sand and concrete. “It’s important to keep the timber on rock foundations, slightly raised off the ground,” Simon says, “otherwise the wood will soak up water from the soil and rot quickly.”
The next step was to build the structure on top of the foundations. On to the rocks, we stacked the heavy 10cm x 15cm thick logs that Simon had ordered from a local sawmill, and began making up the rectangular 3 metre x 2 metre structure. To save costs and time, Simon decided we should build the sauna without screws. Instead, we pinned each layer of timber down into the next with chopped up old carbon fibre tent poles. Each row was slightly offset, so that the beams would interlock in the corners.
The roof was simple: supported by beams at a slight pitched angle, topped with thick plywood, and covered with pond liner for waterproofing, then layered with soil to make up a green roof where plants could grow; further insulating and protecting the sauna.
Once the structure was built, it was time to work on the interior. With thick enough timber walls, internal insulation and cladding is optional. We opted out; eager to showcase the beautiful larch. Next: benches, which should be built out of a softwood that will not get as hot as hardwoods — and therefore remain comfortable to sit on at high temperatures. Cedar is best, but pine or spruce work well too.
Bench placement is very important, says Jenkinson: “Make sure the benches are high enough, so that you sit in the top pocket of heat and steam when you are in the sauna. The rule of thumb is to make sure that on the top bench, your feet rest higher than the top level of the stove, and that your head is roughly two fists below the ceiling.”
Finally, install a stove; the beating heart of a sauna. Lassi A Liikkanen, author of The Secrets of Finnish Sauna Design — a kind of Bible for authentic sauna design and construction, useful for anyone attempting to build their own — says: “Ensure the stove is large enough to heat the space to 60C+, and make sure that on the stove, there are good measures of hot sauna rocks to create steam.”
The result was a traditional, wonderfully simple, log cabin-style sauna, one that Simon will use for years to come. “For me,” says Simon, it’s “a place to put things to bed and a place to think — or in fact, a place to not think at all. Water and heat and steam allow mental clarity to arrive easily.”
Perhaps, before deciding to build or buy your own sauna, it’s best to try a public sauna. Fortunately, there has been an international boom in the popularity of community saunas, from Japan to the UK and Ireland; “Maybe 10 years ago, a new growth for public saunas started,” says Puustinen.
“We have found our growth to be exponential, starting with two saunas in Hackney [east London], says Charlie Duckworth, co-founder of the Community Sauna Baths. “We now have 10, all of which are sold out days in advance, and we have just opened a new facility in Stratford. We have people travelling from all around London to come to us.” They are planning to invite members of the local community to build their next project, as an opportunity to learn carpentry skills.
Olof Duus, of Berlin-based raumlabor, the group of architects behind Göteborg Bathing Culture sauna, says: “Saunas take an interesting place in contemporary society, you go and don’t really do anything . . . but you can’t have your phone in a sauna. This combination is interesting; of sitting, doing nothing, while being disconnected from the online world.”
If, as the leaves fall, the air gets colder and the nights longer, you go to a public sauna and become inspired to build one of your own, it could be worth reading Lassi’s book or joining the British Sauna Society for advice and guidance.
As Jenkinson says, in his experience “conversations in saunas are often a lot more raw than out in the world. The heat of the sauna allows you to feel relaxed and become vulnerable. That state means you can open up a bit more. In my experience, conversations and experiences with others in saunas are more profound and hold a lot more meaning than they would elsewhere in day-to-day life.”
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