Wood burning sauna: feed from the outside or inside?

Hi Glenn,

I discovered your site and appreciate all the information you have here–I discovered that we have a great sauna stove mfg. right here in Minnesota–so that was good to learn.

I’m dreaming of building a wood burning sauna, so I’m looking at floor plans. I see one plan you recommend is to have the stove at the rear wall, centered in the sauna. Does this mean feeding the stove from the outside?

I was in a sauna this fall that had a changing room, and you fed the stove from that room. That seemed like a good idea to me, because the stove was inside…any particular reason for not feeding the stove from the changing room? Maybe it’s better from outside, so you have more room and less mess in the changing area?

Just curious about your thoughts on this as I start my research.

Thanks,

John
St Cloud, MN

Hi John:
Glad you found the site, and glad you find it useful.  it’s nice sharing the joy of sauna.  I particularly enjoy building saunas as you can see.
With regard to feeding a wood burning stove, i am a big fan of feeding from inside the hot room.  In the old days, an outside feed made sense because sauna stoves were not very efficient.  It became a will of sorts, overcoming inefficiency with more logs, stoking the heck out of a barrel stove or home made contraption.
The feed from changing room is a viable option.  It saves a bit of space, and offers heat into changing room.  In my experience, however, this is unnecessary.  Heat gets in the changing room just fine by opening and closing the hot room door.  Further, feeding through a wall requires some elaborate fire proofing and framing around the “throat”.
Today, wood burning sauna stoves are very efficient.  I can start and take a sauna with a handful of firewood tucked under my arm.  Loading from the hot room has never been much of an issue for me.  BONUS:  many wood burning sauna stoves, Kuuma included, offer a glass window.  A wonderful aura, turning the light off in the hot room and seeing a warm glow reflecting off tongue and groove cedar in the sauna.  Magical.
Hope this helps, please stay in touch.
g.

The Kuuma Stove.

Most folks in Tower, MN will tell you that February 4, 1996 didn’t feel much different than any other cold winter day.  Yet for meteorologists and weather enthusiasts around the country, this day is marked in history as the coldest day in North America, -60f.  To get a handle on just how cold this is, consider:

  • 60 degrees f. – golf weather, maybe a long sleeve shirt.
  • 0 degrees f. – f*** ing cold!  Unexposed skin subject to frostbite in minutes.
  • -60 degrees f. – UNFATHOMABLY cold.

A cold climate with lots of innovation.

Tower, Minnesota is the climate where three generations of Lamppa’s have been building sauna stoves.  3rd generation Daryl has spent countless hours and many years refining the design of Lamppa’s wood burning sauna stove, called, simply, The Kuuma (Finnish word for hot).  During one visit, he showed me his “graveyard” of spent parts, bringing to mind Thomas Edison’s line:

"I have not failed 10,000 times. I have
successfully found 10,000 ways that will not work."

Authentic and efficient.

Daryl Lamppa’s dedication to design and function is matched with his authenticity.  He was building “green” before it was a marketing word.  He understands exactly how wood burns, and the fact that 70% of a wood’s BTU potential is in the smoke.  Further, smoke escaping up the chimney is dangerous.  Smoke leads to creosote build up, a leading cause of fires.  Facing this issue head on, Daryl kept working to maximizing gasification, the burning of smoke.  His stoves are very safe and very efficient.  Authentic wood burning sauna enthusiasts are amazed at how, with a few sticks of firewood, a Kuuma stove can throw so much heat for such a long time.  Further, looking up at the smoke stack, it’s often hard to tell if the stove is on or off, as once the stove is up to temperature, there is no smoke coming out the chimney.

A factory set back in time.

Lamppa Manufacturing is a production facility set back in time.  It is a no frills, purely functional production center.  Raw steel comes in through one door, and Daryl’s staff of a few long standing employees manually cut each piece, welding, assembling, until what appears out the same door is a work of high quality with beautiful simplicity.  This is how factories functioned through the industrial age.  Lamppa’s factory floor boasts nothing shiny or new, just tried and true machinery.

Quality is easy to see.

One only has to look at the welds: straight, true, uniform, to understand the attention to detail and craftsmanship.  The Kuuma stove is a beast.  1/4″ steel.  Sure, thinner steel could work, but Daryl isn’t into maximizing gross profit, just wood burning efficiency.  The stove will outlive most people.  A Kuuma will never end up in a landfill.

Humble and unmoved by hype.

Like discovering a fabulous restaurant, one is torn with keeping it a secret, or sharing the enthusiasm with others.  I am reminded of Joe Seliga, now deceased, a master canoe builder from Ely, MN.  In his one stall garage just up the road a piece from Lamppa Manufacturing, Joe spent most of his life building hand crafted canoes of impeccable quality and design.  I visited Joe one day soon after folks from New York Times Magazine ventured out to write a story about his craft.  He got a chuckle about the photographer taking shots of his paint dripped cement floor.  Joe Seliga was humble and unmoved by being “discovered” nationally.

These are artists and craftsmen. Folks dedicating their life to a skill.  Perfecting their design.  Working in a rural environment free from marketing hot air and noisy SUVs.  Maximizing efficiency through excellent design.  Building with their hands.  Putting their name on their product.  Standing behind their product, and proud of what gets shipped out the back door.

Can eucalyptus oil start your sauna on fire?

Picture courtesy Vincent Megaides Source: The Daily Telegraph

Maroubra Seals Sports Club in Sydney, Australia, was up in flames Friday evening, and Pete Reid, General Manager, seemed mightily pissed off:

“The fire started in the sauna. I’m of the opinion it started by people putting things on the sauna – eucalyptus oil – which they have been told not to do,” he said.

“People just can’t be told – even thought there’s signs and everything else.  That’s the end of the sauna. There won’t be any more at Maroubra Seals.”

What a shame.

All (authentic) sauna stoves are made to take water. Faulty electric sauna stoves can short out from excessive water dousing.  A wood burning sauna stove won’t short out and is thus safer than an electric sauna stove, how ironic is that?

 

 

 

What’s for dinner? Loyly rock soup steam pot.

Guest post from Andrew who has installed a conventional wood stove for his sauna, and has found a simple solution to the loyly (steam from water being tossed on sauna rocks) quest.  So far he has not had any problems with his common steam pot that sits atop the wood stove.  He filled it with rocks from his nearby stream to make sure the loyoly is true (and from his land).

Only limitation is the amount of water you can pour on it. 1/4 cup or less to keep it from boiling over.

Steam soup is ready!  ahhhhhh

An efficient way to chop wood for your wood burning sauna, cabin sauna, or fireplace.

Ever seen that documentary film about the guy who builds his own cabin in Alaska and hunkers down for the winter?  They show it on PBS from time to time, it’s called Alone in the Wilderness.  This 0:58 video shows us similar resourcefulness, and gets us all charged up for chopping wood, stacking fuel for our wood burning saunas.  An efficient wood burning sauna stove blasts heat that radiates through the body.  Here’s an efficient way to source your BTUs:

The Kuuma Sauna Stove detailed in an informative video

Look out Hollywood!  Daryl Lamppa is turning down offers from Hollywood to stay on board as CEO, Chairman, and chief welding operator for Lamppa Manufacturing.  This is great news for us sauna enthusiasts.  Below is his Hollywood screen test, where he details the Kuuma sauna stoves.  We have detailed the quality and performance of the Kuuma sauna stove many times (here and here) as we are loyal fans.

Investing in a Kuuma sauna stove is one of those rare treats.  It enhances the sauna experience for many reasons:

  • The sauna stove performs perfectly every time.
  • The quality is unmatched anywhere in the world.
  • Daryl’s pride and workmanship is felt with every sauna.
  • The stove is built like a tank.  It will outlive you.
  • Three generations of sauna building have helped perfect it’s design.

In a world of outsourcing, mass production, cutting costs, consider for a moment how rare is it today to buy find a quality product and actually talk to the man who not only had a hand in it’s construction but who actually designed it!?

Like hand made kitchen cabinets, or your favorite microbrew, or a Silega canoe, it’s one of those rare purchases where you smile every time you look at it and thank whoever or however you found out about it.  Whatever the freight is to get one delivered to your sauna build, just do it.  You’ll be thanking us by the end of your first sauna round.

Wood or Electric sauna stove?

I have had many emails on this question.

  • “I’m building a sauna and can’t decide whether….”
  • “Glenn, you mention an outdoor wood burning sauna but we have an ideal place in our basement for….”
  • “My husband wants a wood burning sauna, but i’m worried about…”
  • “I grew up with an old school wood burning sauna, and now it’s my turn to build my own….”
  • “Glenn, I have plenty of access to wood, and enjoy the wood cutting experience, yet I’m concerned that my wife won’t want…”
  • “What about the smoke, will my neighbors…”
  • “I’ve heard that a wood stove can take hours….”
  • “I can hook up 220v heater because we finally pulled out our hot tub bacteria petri dish…”

In defense of electric heated sauna stoves:

  1. Easy to use: Flip a switch, or use the programming device.
  2. Easier to install, no chimney stack.
  3. No red tape with insurance company or fidgety building inspector.
  4. Sauna stoves heat rocks, who cares how they’re heated?
  5. Cleaner, easier to maintain.

In defense of wood heated sauna stoves:

  1. Authentic, natural way to heat.
  2. Brings forward the ‘up north’ cabin vibe.
  3. Promotes and outdoor experience and the concept of escape.
  4. Negative ions are realized through wood burning.
  5. Wood burning saunas vent better, more naturally.
  6. More radiant heat for better “ahhhh” loyly production.

I didn’t list that electric sauna stoves heat quicker, as I can personally attest that my wood burning saunas (all three) heat up about the same time as electric sauna stoves.  Nate’s Firestarters help, custom made by a Barton School student.  They are so easy, an 11 year old can do it.

Wood, electric, let’s not debate forever:

NOW IS THE TIME FOR YOUR OWN SAUNA.


Road testing your sauna in the cold

Sauna: test it in cold weather

It’s been really cold here in Minnesota.  Just like with car batteries, this is the kind of weather to really get to know your wood burning sauna stove in your outdoor sauna.  In normal weather, any old stove with any old type of wood can get any old sauna up to 140 f (60c).   With time and determination, a combination of decaying pine branches smoking along in some home made metal box stove in shoddy insulated sauna room will eventually provide enough BTU’s to offer a sweat and some form of sauna.

A more serious sauna environment

Here in Minnesota, we don’t mess around with heat.   We can’t afford to.  It’s been below zero (-20c).  It’s great sauna weather.  And no matter where you live, you shouldn’t mess around with a lame sauna stove, or bad wood, or a poorly designed sauna.  Doing it right doesn’t mean you have to spend a lot of money, either.  This is the type of weather where you can tell how good your sauna stove is working, or where there’s a crack in your sauna door and the difference between burning pine and oak.

First things first, your outdoor sauna

I’m a big fan of good basic insulation, and a bigger fan of foil vapor wrap. Batting is cheap.  You can frame with 2×4.  Keep your ceiling at 7′ and if you go with 8′ ceiling, that’s fine, go with 3 benches but keep you cube small.  It is a lot easier to heat a small room than a big room.  This isn’t a suburban game of sheet rock palace, square foot fever.  This is an example of less being more.

Second, know your wood

If you’re heating with an electric sauna stove, you can move on.  However, us wood burning purists like to know where our BTU’s come from.  We are like microbrewers and gardeners.  Some of us have beards.  We stutter when we say ‘sustainable’, and some of us mumble words like ‘renewable’ in our sleep.  Up north, I burn birch almost exclusively in my cabin sauna but here in Minneapolis, it’s all across the board.  When I hear a chainsaw, i’m like a dog who hears another dark barking.  I chase after the sound and newly felled wood.  Many are more than happy to part with their tree cuttings.  Stay well clear of Elm (ash bore) but here are my favorites:

  • Maple: dense hardwood.   Harder to light, but burns long and hot and slow.   Great to add to a hot fire.
  • Pine: Burns fast, produces more ash.  Great starting wood.
  • Oak:  My favorite all around burn.  Megga BTU’s, especially well aged red oak.
  • Birch:  Fantastic for saunas, burns hot and bright.  BONUS: birch bark is nature’s gasoline.

Third, get a real sauna stove

I’m biased.  I own three Kuuma wood burning sauna stoves. They are the best sauna stove made.  I can bring my backyard or cabin or mobile sauna from 0 degrees f. (-18c) to 130f (54c) in about half an hour with 3-4 good pieces of wood.  Then, after pulling the hot coals forward, I’ll add another stick or two, and bring the sauna to 150 degrees f. (65c) a few minutes after that.  I can manage the fire, manage the burn rate, and take a 2-3 hour three round sauna at around 170 degress f. (77c).  All that with an armful of well season firewood.  sussusstainable.

How do you road test your sauna?

Wood burning sauna stove: load from inside or out?

When building a sauna, there are three ways to consider setting up your sauna stove:

  1. Load wood from the outside
  2. Load wood from the changing room
  3. Load wood from inside the hot room

Options #1 and #2 involve using a ”throat” add on to a wood burning sauna stove.  Also, one needs to brick around the throat and sauna, usually a three foot border, for fire retardant.   In the old days, most saunas were built #1, loading wood from the outside.  The main reason for this is that old saunas were inefficient, basically home made iron boxes that burned hot and fast, requiring a pretty much constant supply of firewood.  Finnish ingenuity gave way to the idea that the door to the sauna stove could be steps away from an outdoor wood pile.

As stoves became a bit smaller and somewhat more efficient, people began building wood burning saunas to feed from the changing room.  The theory here is that a small amount of firewood could  be kept dry in the changing room and added to the stove from there.  The main advantage to #2 is that the sauna stove can provide some heat to the changing room.  It is estimated that between 10-15% of a sauna stove’s heat comes from the front of stove.

#3 is my choice.  Today’s sauna stoves are very efficient.  The Kuuma Stove is so efficient that I can take a sauna with 4 pieces of firewood.  By feeding from inside the hot room, I capture 100% of the heat in the hot room, and don’t have to mess around with extensive brick framing.  Also, I can monitor the fire from the sauna bench.

Wood heat vs. electric heat

Is there a difference?  Tell me your opinion.

Considering whether to build a wood burning sauna or an electric sauna?  You may want to read below.. I’ll post all comments.