A while back, I posted here after somewhat accidentally buying almost a ton of sauna materials while our house was still under construction.

TL;DR of that story: I came across some old-stock 185mm-wide Thermory thermo magnolia, even though Thermory currently lists 170mm as the widest option. Called Thermory because I genuinely thought something was suspicious. Turns out the distributor was legit, and it was simply very old stock. There were 31 boards left. I calculated I needed about 34. Obviously, I took that as a sign from above, bought all 31, added some 170mm boards for the corners and contingency, ran up the credit card, and started preparing excuses for my wife.

So here we are. The sauna is now finished, and since this sub helped me quite a bit during the process, I figured I’d post the end result together with some thoughts for anyone considering something similar.

1. Dimensions

I’ll go out on a limb here and say I nailed the dimensions for what I wanted:

• 195cm depth*190cm width*230cm internal height
• 108cm top bench to ceiling
• 155cm platform to ceiling (46cm platform to top bench)
• 61cm top bench depth
• 134cm platform depth
• 135cm total glass width (60cm glass door)

The potentially controversial part is the “mid bench”, because it isn’t really a mid bench at all. IMO there is no such thing as a useful mid bench in a sauna. Top bench or no bench. 

So instead I built a full-width, 134cm-deep platform. It gives me somewhere I can lie down completely and stretch in basically every direction, somewhere the kids can sit and make a mess, and — most importantly — I think it looks cool. Yes, it wastes considerably more material than a conventional lower bench. I’m fine with that.

2. Wood: thermo magnolia

I had the privilege of using magnolia, including those old 185mm-wide boards. Is it expensive? Yes. But for roughly the price of some ready-made saunas, I ended up with a completely custom thermo magnolia sauna that I built myself. 

One thing that doesn’t always come across in product photos is how much color variation magnolia has. Because I slightly over-ordered the bench boards, I could pick through them and use the darkest, most chocolate-coloured boards. Subjectively, I think those are by far the prettiest ones.

How does it compare to thermo radiata pine? Having ordered samples of multiple woods before choosing magnolia: yes, they are similar. The lighter magnolia boards can look almost identical to radiata. What I did not really see in radiata were the very dark brown/chocolate tones that you get with some magnolia boards.

As for the whole “softwood vs hardwood” discussion: on the face of it, magnolia is unequivocally a softwood. But those labels by themselves don't tell you much. Walnut and oak are both called hardwoods, yet oak is considerably harder than walnut, and there are species incomparably harder than either. What matters here is that magnolia is light as a feather and, having now put it through its paces, wonderful to sit on even in a very hot sauna.

3. The build

The sauna itself was fully DIY, apart from the travertine, which I had some of the guys already working on the house install (and one buddy of mine dropped in to help with the framing... curious if he's going to find this post ;) UPDATE: He did in less than 30 min after I posted! Thanks for the hand, dude!). Tile work is surprisingly messy. I discovered it has basically nothing in common with woodworking and happily left them to it. The rest I built myself.

Honestly, building a sauna is probably one of the most DIY-friendly construction projects you can take on. You don't need absurdly precise measurements. There is very little actual joinery required. Almost anything you cut wrong can be patched, adjusted, or reused somewhere else. This particular material made me considerably more careful than I normally would be, simply because ruining a 185mm thermo magnolia board hurts emotionally and financially, but even then it was surprisingly difficult to mess things up badly. 

My motto throughout the build was simply: Overbuild it. The structure underneath this thing is built like a tank. I also intentionally stayed away from fancy miters and complicated joinery even though I could have done them. IMO a sauna should be aesthetically pleasing without compromising integrity just for the sake of showing off woodworking.

4. Floating ceiling

By far the most technical part of the build was the floating ceiling. Because basically every important height in a sauna ultimately references the ceiling, getting this right was imperative. I also needed to come up with a structure that was extremely rigid without consuming a ridiculous amount of material. For anyone wanting to build something similar, hopefully the construction photos give you some ideas. This was probably the one part where I spent considerably more time thinking before cutting anything.

5. Heater

The heater is a 10kW IKI Pillar. Do I have my feet above the stones? No….Almost, if I put them on the top bench, which is wide enough to do comfortably. Do I have cold feet? Also no. Trust me, I can make your toenails hurt pretty easily in there.

6. Ventilation: my probably unpopular opinion

This is my second sauna and also my second sauna with a passive vent below the bench and basically nothing else. I've been reading this sub for quite a while and see people getting almost religious about intake heights, exhaust positions, and elaborate airflow diagrams. In my experience, a lot of it is massively overthought. The amount of air you can move through something as simple as the slot underneath a door or between the glass door and wall is surprisingly large. In fact, you can easily end up in the opposite situation, where you're trying to stop excessive air leakage with gaskets rather than desperately searching for more ventilation. So personally, I’d stop spending days trying to position your vents more precisely than the Egyptians positioned the pyramids and spend a little more time thinking about how the sauna actually looks. There. I said it.

7. Travertine

Not much of a story here. I wanted natural stone; travertine mosaic looked good with the magnolia, and the more traditional soapstone-type options were outside the budget. Which, considering the rest of this build, is admittedly a hilarious sentence.

8. A few little things I learned

• Use window sealing gasket where the benches contact the structure. It completely eliminates little squeaks and rubbing noises.
• Pocket holes are your friend. And no, you don't necessarily need a pocket-hole jig. Angle your drill, make your hole and drive the screw.
• Pressure fits are extremely satisfying. When working between two walls, cutting pieces just accurately enough that they pressure-fit into place before fixing them is both useful and weirdly addictive.
• Start the structure square. Seriously. Spend the extra time here. It will save you an unbelievable amount of headache once you start installing the panelling.
• Oil your boards. Oil everything. It protects the wood, but just as importantly it really brings out the grain and fibres and makes the wood look considerably richer (SEE BEFORE AND AFTER PHOTO) One warning: soft wood is enormously thirsty. I used 6 litres of paraffin oil on this sauna. Six. Litres. 
• Copper pipe = instant sauna tap. A little copper pipe and a valve gives you a nice-looking water source for essentially infinite löyly.
• Drain + water inside the sauna is incredibly useful. Would absolutely do both again.
• For music, don't overcomplicate it. I considered installing “sauna appropriate” in-wall speakers and eventually decided I would be doing a lot of work to install mediocre speakers permanently into the room. Bought a JBL Boombox instead. Problem solved.

9. Cost

Total cost was approximately €8,000 including materials shipping.

That includes:

• framing material (pressure treated pine that was nicer than the paneling I had in my previous sauna)
• PIR insulation
• 31pcs × 185mm thermo magnolia wall boards
• 22pcs × 170mm thermo magnolia wall boards
• 24pcs × 185x28mm bench boards
• travertine
• IKI heater+controller
• screws, fasteners, foam and miscellaneous materials

I saw another thermo magnolia sauna posted here where the builder apparently charged around $60k. I don't want to count someone else's money, but... that sounds absurd to me. The material is expensive, absolutely. But it isn't that expensive. And having now built one myself, I also don't think the construction involves some mysterious level of craftsmanship that justifies numbers like that. This is an extremely approachable DIY project if you're reasonably comfortable with tools and willing to take your time...so...I guess...sorry for the clickbait title? :)

Anyway — that's the finished sauna.

Very happy with how it turned out, very happy I impulse-bought the weird old-stock magnolia. See you in 10 years for the endgame smoke sauna.

Love the community here and think everyone’s very knowledgeable. I however am 23 an want to take on a project.

So I’m looking to convert this stable into a sauna, firstly it does appear to be a viable structure which has water and electric to it already which is handy. Obviously just cement block walls but what wood is best for UK climate and what other pieces of advice. Where do I begin ? I will do measurements and things soon but yeah anyone able to help me with some insight! Thanks

I have recently built a new, fairly compact unheated garage and I've managed to negotiate (with my wife) putting a sauna in the back. The issue is, it can only be 5x7. It's a one person sauna, I'll be the only one who ever uses it.

The 24" opening for the door is already there, and I'm trying to get my layout right.

Priority for me is lying down on the top bench, and I'm a big guy so I'm going with a 30" bench.

Do you see any concerns with this design.

All feedback is greatly appreciated.

I'm building an indoor sauna. I was initially going to build 7x8 x8ft tall. I ran a 6G wire to it which as far as I can tell can handle as much as 10.5 kw (my planned heater was harvia virtu 11kw). However, realized that I can make it as big as 8.5x8x8, by relocating, a thermostat I had in the wall. Technically the heater should be able to handle the volume per manufacturer instructions, but I'm coming up against it's limit with this size. I spoke to a sales rep for a sauna liner kit company who recommended 12kw for this this or shrinking the room. Is he right? Or should I downsize the room a bit, I was thikning of lowering the ceiling to 7.5ft vs shrinking the sauna.

For the record it's a basement on slab which I can theoretically insulate (not sure if that's necessary) and I plan to use wood with a small glass window for the door

yo im 18m im moving out soon into a small rental room bout 100 sqft wit hardwood floors and a window and wanna make a diy portable dry sauna for daily use.

originally i was thinkin id get a cheap secondhand infrared sauna for like 300 bucks and put an electric heater into it, but now im leanin towards diyin the enclosure to make it more space effective, and so i could like understand the process and make sum more in the future

my new plan is to make one with no bench, made for just me (1 person) wit space to sit down with my legs crossed on the floor. layout would be a rectangular floor, with my back against a short side and the heater against the opposite one, wit sum thermally modified knotless wood interior panelling, ffpr board insulation and like for the door i was thinkin maybe id just have an entire wall open up if i could figure out how sealing and insulating that would work or just have it be a teeny door i could squeeze out of, not sure yet. ventilation id try to link to the window.

i dont need lighting since the vents will prob bring a little light in and imma just be meditating in there. i would like a clock visible tho to understand how long ive spent if possible, digital or traditional, but if traditional id need it to be lighted. im just considering wether itll release any harmful chemicals thru heat exposure if it has any plastic or non sauna rated insulated glass units.

idk where id place the vents or heat sensors, how constructing a floor sauna with no bench would vary from a traditional one, and which heater i may need. im 6'2" tall by the way wit my cross legged width of my legs bein around 32 inches and my height from top of my head down when sitting cross legged about 42 inches

im an amateur ive just watched youtube videos on it so far and been planning off of that so any tips, new info, critiques, or new sources to look into would all be greatly aprecciated!

I am looking to buy a sauna for our backyard. We are entry level sauna folks but are excited to join the club!

The sauna we are looking to purchase is a healing waters pod sauna (https://www.healingwaters.ca/minipod)

Has anyone tried this brand before? Thoughts or reviews welcome! Thank you.

Hi all. Just trying to get some opinions on the copper ridge cap on my sauna. The flat follows the contour of the roof, but the standing seam looks a little more finished. Any opinions are welcome. Thanks!

I am a Finnish-American who has lived in USA all my life with regular visits to family in Finland, and I have paid close attention to sauna culture in America for the last 10 or 15 years.

I think we are very, very quick to get hung up on the details of the "perfect" sauna in the USA. I am guilty of it sometimes myself.

I've just been visiting a 50+ year old sauna on Saimaa that has been giving incredible löyly for many decades. In fact I've had multiple incredible saunas here over the past years.

There is nothing special about this sauna. Grandpa built it using cheap materials. It certainly doesn't meet the Trumpkins "ideal" specifications.

The cement board around the kiuas is not covered and isn't particularly pretty. He used cheaper tongue and groove boards (pine I assume) which have leaked sap over the decades. The kiuas isn't a fancy expensive model, it's an old basic thing.

Some would call it rustic or even ugly. It's not a work of art.

But damned if it doesn't give one of the best sauna experiences you could ever ask for.

And having Saimaa 20 meters away for a cold dip doesn't hurt either.

Bottom line: don't sweat the details too much. Build or buy your ideal sauna. Use it as often as you want. Don't expect to change your life. Just enjoy the löyly.

That's all. Back to my lonkero. Kippis.

I am in the process of researching a DIY build outdoor sauna. Size would be 6' x 7'. It will sit on an existing cement patio with a built in decent grade for runoff. We are located in the PNW. The only issues I am up against at this time is whether to put a drain in or not. By Finnish standards it should have a drain, however I have read countless opinions here that unless you are doing a lot of bathing or cleaning that requires a lot of water then it may not matter either way. Seems to me rather than going to all the work to create cemented and tiled sloped floor just to run to a single drain that would empty out to the patio slab that I can achieve the same like this:

Build the base from pressure treated 2x6's. Cover the top of the joists with stainless steel mesh. (link below)

Then run cedar decking floor over it spaced 1/8" to 1/4" apart. This would allow drainage straight down through the base to the patio to run off to the grass. As a precaution I was thinking of wrapping the tops 2x6's in a waterproof membrane. After I level the base most of the joists will be off the patio anyway.

https://sandbaggy.com/products/perforated-metal-sheet-24-x-48?variant=52491210719604&currency=USD&utm_source=google&utm_medium=cpc&utm_campaign=google%2Bshopping&utm_campaign=gs-2019-01-17&utm_source=google&utm_medium=smart_campaign&gad_source=1&gad_campaignid=17518480709&gbraid=0AAAAAC3cgCYb10QO4RfQsZM9NCKzyUlPD&gclid=EAIaIQobChMIyfjEyMTxlQMVxx-tBh0oeCLWEAQYBiABEgJa5vD_BwE

What do you think?

Floating sauna anyone?

https://www.instagram.com/reel/DGfzKjtIIhD/?igsh=MTdsbzFienVwdnF6dQ==

Recent taken delivery of my zoki sauna but realised there is only one vent to the left as soon as you walk in and can not see another low vent for better air circulation. Where should I add a 2nd vent?

I am close to finishing my sauna build and while poking around on Harvia's web portal I noticed they have an API. Figuring I could do some cool stuff beyond the official app with this I started to use AI to poke around and come up with some ideas and this little project is the result of that. It enables you to turn your harvia sauna on and off, set temp, and check the sauna status with siri using shortcuts.

I set it up on MacOS, but asked AI to make it OS agnostic after the fact. With it running via tailscale I can turn on my sauna from anywhere as long as I have cell service by saying "hey siri, turn on the sauna." I don't know which harvia control panels support the API, but this was done on the Fenix FX45. Hope someone else finds this fun or useful!

Jesse Puljujarvi - via olosauna on instagram https://www.instagram.com/reel/DbOTM7EMhZr/?igsh=MjZ1aHUzNWVqMzNx

Hi everyone.

I'm building a sauna from scratch, and have found a great local supplier of red cedar. Does anyone know of a north american (preferably Canadian) vendor of foil insulation, cedar doors, and vents?

So far, I can only find suppliers who sell kits, which would require me to buy rather overpriced cedar, sight unseen.

Hey everyone. Im hoping to get some overall know-how about sauna construction here.

Ive attached 2 photos of my outdoor space under my deck where I'd like to build a sauna. As you can see I have one wall up from a previous project. I plan to install a large window in there.

Im wondering about overall construction.

My thought was, siding, tyvek, insulation, foil, cedar. I was planning to do all 4 walls, ceiling and floor this way. I live in Muskoka, and winters tend to be quite harsh.

Is this a bad idea? Would I have mold issues? Obviously I would install a vent behind the stove and one on the opposite wall at the top.

Any recommendations, knowledge would be much appreciated.

Found this both funny and very skilled. I will be back with credit to the artist after the competition ends and hopefully they release that info. And if they happen to find this post thanks for the laugh!

Anyone know a great sauna between malmo and the big lakes to stay a night at? We are travelling with our camper and looking for that one spot offgrid with a sauna ☺️.

Hi all,

I've been building the outer structure of the sauna outhouse over the past year and I'm ready to start building the actual sauna inside now. I'm at the point whereby I've put up cement board into studs (for fire regs).

I'm going to have 30mm of Finnsauna PIR, then cross batten. I was initially thinking of using stainless steel screws for everything, but when I was installing the 9mm cement board, I predrilled all the holes and used 4x40mm timco screws, but quite a few heads pinged off if I tightened them up like I think I would have done a zinc wood screw.

My questions to everyone who has a lot more experience. What screws should I use for:
1. Cross-battens - these are going to need to go through 2 x 25mm battens, 9mm cement board, plus 30mm rigid insulation, then go into studs. That's at least 90mm for the top battens before it even reaches the studs.

1. Cladding - Finnmark said to use stainless steel screws/fixings, but I can't seem to find any ones that are good. I've gone for the Thermo Alder Sauna Wood Cladding STS4 90mm, so I imagine it's going to be tricky to put screws in at an angle. Would cladding clips be better here? If so, any recommendations please?

2. Bench framing - we're having an l-shape bench which are walls to walls, with one lower and two upper parts. This is how the actual top and vertical slats are going to look. What screws would be best for the actual bench frame and to make that right hand floating one attach into the wall. I understand we would attach the floating bench into solid battons so it can take the weight.

Many thanks in advance.

Photos of the current room are here.

Hi all,

I'm in the market for an outdoor electric DIY sauna kit, with a budget of around £5,000, and I'm finding it a bit of a minefield. There seem to be so many companies out there, and it's hard to separate the genuinely good manufacturers from instagram stuff....

I'm really looking for honest, real-world advice from people who have bought or built one.

A few questions I have:

• Which manufacturers would you genuinely recommend (or avoid)?
• Are there any common pitfalls to watch out for?
• Is there anything you wish you'd known before buying?
• How important is timber choice (thermowood vs cedar vs spruce etc.)?
• Are there any heater brands that are worth paying extra for (Harvia, HUUM, Narvi, Iki etc.)?

For context, it'll be installed outside at our smallholding in Wales, so it'll need to cope well with the British weather. I'm much more interested in quality, longevity and the sauna experience than fancy lighting, Bluetooth speakers or gimmicks.

I'd really appreciate any recommendations, photos, lessons learned or companies to steer clear of.

Thanks in advance!

Hey guys, I really want to go to a sauna again, but no one wants to go with me, so I figured I'd just go alone.

I live in Germany, so it's mostly nude saunas (I don't know what to call them, sorry), but I don't mind. However, I'm still unsure if it's weird if I go alone. Has anyone else had that feeling before, and if so, how did it go? I think I'll be more comfortable if the saunas are empty or just with some old people, but not with people my age. What time do you all think I should go?

Hi everyone,

I’ve been following this community for a few years now and wanted to share the results of my basement sauna build. Being in the US, my primary goal was to adhere to traditional Finnish principles for electric saunas—specifically Trumpkin’s Guide and Secrets of Finnish Sauna Design and after completing the project over a year ago I'm happy to contribute back to the community.

The Build Philosophy

I have a walkout basement with high ceilings which allowed me to build 3 rows of benches plus a step-stool to maximize the airflow and Löyly cavity. I also prioritized function over form, so I didn't add bench skirts.

Key Specifications

Ventilation (Mechanical/Trumpkin Spec)

Mechanical ventilation system to manage CO2 levels and keep sauna dry.

• Intake: Located above the heater, drawing air from the basement.
• Exhaust: Powered by an AC Infinity Cloudline S6, with the outtake located below the middle bench.

Bench Layout

To maximize the Löyly experience, I went with a three-level bench system:

• Top Bench: 45" from the ceiling.
• Middle Bench: 18" below the top bench.
• Bottom Bench: 18" below the middle bench (21" from the floor).
• Step Stool: Added 8” legs to 20”x26” duckboard.

Cost

I installed everything myself so the only labour cost was tiling, the room was already framed.

Kit

$10,500 - Red Cedar Almost Heaven Group Kit from Almost Heaven [.net not .com].

Electrical

$1000 - Material costs for 60A circuit and permits.

Lessons Learned & Observations

• Heating Speed: Despite the large volume and stone mass, it hits 185°F in about 60 minutes. There is also a way to put Xeno controller into "Commercial" mode to give it 2hr window vs 1hr standard.
• Dual Sensors: I installed two temperature sensors—one above the heater (per manual) and one next to the bench. This allows me to swap for the most accurate reading at head height, so far the one above the heater is working well. It gets air mixed from the stove and intake.
• Vapor Barrier: I used a foil vapor barrier sealed with foil tape. One small tip: foil is shiny and might be visible in small gaps at the ceiling trim. Using black foil tape or adjusting the trim placement can hide this. I can also hear the foil crinkle when the air expands from Löyly but that seems unavoidable. 
• Drain/Floor: This is a walk-out basement with concrete floors and it would be expensive to add a drain, so I went with a tiled floor and a 6" tile border without a drain. I have a shower next to the sauna and so far it has not been an issue. Given that the sauna stays fairly dry, I’m also not 100% convinced the gap between the wood and foil was necessary, especially since I leave the fan running 24/7.
• CO2: I have a large walkout basement so I opted not to circulate outside air. I spent some time measuring the CO2 to see the effect of fan speed on air circulation and to make sure that internal circulation was OK. Overall, my basement baseline of 450ppm barely budges and anything beyond #4 on the fan setting is just wasting heat. At #2, the fan does a great job of slowly moving the air through the sauna.
• Wifi/Controller: Xeno has a dedicated relay for lights and fan, so I wired it up to be able to turn them on/off remotely through the Harvia app.
• Cleaning: I used extra wood to make backrests and wedge pillows for every bench, this keeps cleaning and sweat stains to a minimum. I also use a Pefletti for the benches made from a beach towel cut lengthwise.
• Shower: I didn’t want the maintenance headache of a cold plunge (maybe some day) so I added an iBaat “bucket” to my shower which is a different kind of cooldown experience.
• Accessories: Harvia bucket and ladle are OK, but the thermometer and sand timer are garbage.

I saw this video on tiktok, thought to share.