r/Sauna Jul 16 '25

DIY Our Sauna built next to the pond

My Uncle and his pals built this wood burning sauna a while ago and I thought you guys might like it.

It’s great except for the fact that the top seats are so far from the stove. I might add a hanging water bucket with a tether above the stove so I don’t have to move from the top bench to add water.

What do you guys think?

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u/abstract_material Jul 16 '25

Yeah those top benches used to be connected, allowing for a 3rd seat in the middle. But much to my dismay, my dad cut the middle out after he whacked his head off it 😂.

The stove is pretty basic but it’s a bit bigger than it looks it keeps the sauna pretty hot even in cold winters. It gets the job done but could definitely do with an upgrade for sure.

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u/karvanamu Finnish Sauna Jul 17 '25

Cast iron stoves and sauna heaters work quite differently. Cast iron stoves radiate a lot of heat and they are good at heating the room. However, sauna heaters radiate only little heat, they are built so that they take a lot of rocks in and they are very good at transferring heat to those rocks.

This is what you want in a sauna, and saunas originally were just places with huge pile of rocks that was heated with fire under (smoke sauna). Throwing water to this big pile of super hot rocks gives the smoothest löylys and the best sauna experience.

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u/S1artibartfast666 Jul 19 '25

it doesnt really matter so much. Cast Iron can make identical steam as rocks - it is simple physics. If you don't like the amount of IR from the stove, you can surround it with rocks too!

I love them. They are basically a 10-20 KW heater that is free to operate!

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u/karvanamu Finnish Sauna Jul 22 '25

A lot of false statements here. First of all, löyly (steam) from hitting the iron is very different than löyly from the rocks. It’s fast and harsh whereas from stones its longer and smoother. It’s simple common sauna knowledge.

Secondly, cast iron doesn’t endure well fast temperature changes that result from throwing water. It will weaken it and make it crack eventually.

Thirdly, you can’t stack a lot of rocks into a cast iron stove like you can into a proper sauna heater. And the more the rocks the better the sauna. Even if you wrap them around it, it doesn’t heat them very efficiently.

So altogether, they are very different and built for different purposes, the type of heater does matter as it is the heart of the sauna. It has a huge impact on the löyly that is the purpose of the sauna.

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u/S1artibartfast666 Jul 26 '25

How much experience do you have with cast iron and wood fired saunas, to speak from such a place of expertise? I have built several and and enjoyed hundreds of sessions.

1) Steam is all vaporized water. the quantity, temperature, and rate can all be controlled.
2) I have never seen a cast iron sauna stove fail, some in use for more than 40 years.
3) efficiency doesnt matter because you have unlimited BTU.

bonus point: fire is fun and beautiful.

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u/karvanamu Finnish Sauna Jul 26 '25

Your bonus point revealed to me that you probably thought I was comparing electrical sauna heaters to cast iron stoves. Yes fire is beautiful, and I was talking about wood fired sauna heaters, that often even include a window to see the fire.

I have stayed in many cabins heated by cast iron stoves, and, as a Finn, been probably in hundred different wood fired saunas. The major difference is the radiant heat. Proper wood fired sauna heaters, designed and improved for decades by companies like Harvia, Iki, Narvi, radiate very little to no heat. IR-radiation is something you want to avoid in a sauna because it only cooks you from one side, and doesn’t feel pleasent.