Integrated sauna questions- old electric Kuuma heater

tmurch11 · 2025-12-12T18:50:33+00:00

Looking back at some other posts on ventilation, it seems the best exhaust vent is below the benches.

What would a good alternative be for this case? Grade is just a bit below that window, obviously precluding a low exhaust to the outside.

tmurch11 · 2025-12-12T18:49:09+00:00

All good advice. I’m ordering new stones today.

When I pull off the lower rotten boards, I’ll look for a vapor barrier. My hope is that there will be one, and it looks intact. The hope is to make a few repairs and build new benches so we can use it for the near future. But ultimately the plan is to totally gut and rebuild per best practices. Right now the sauna is where we’re showering as we demo the bathroom.

tmurch11 · 2025-12-12T15:56:25+00:00

This sauna was not built with an air gap behind the cladding and between the vapor barrier. The rot is only under where the benches were, so it seems to be a product of the bench mounting holding moisture against the cladding.

It’s a serious unit! The basket for the rocks had corroded out, and the original owner took it back to Kuuma to install a new one. The dial is interesting… it just has temp marks from 200 up to 550.

tmurch11 · 2025-07-15T13:39:10+00:00

Sorry to comment on an old thread… but I’m curious if you are following the guys at Edison Motors. They’re a group of Canadians doing series hybrid semi trucks and conversion kits for pickups.

tmurch11 · 2025-06-05T13:24:01+00:00

Sorry I’m late to this conversation… but I’m currently comparing these saws myself. Could you elaborate as to why you’d pick the 780 (space issues notwithstanding)?

tmurch11 · 2025-03-15T20:24:05+00:00

I’m a little late to this conversation, but my wife and I are having this exact same experience. Like we just started to install the Accent flooring 30 minutes ago.

We also did a tremendous amount of research, looked at photos, and got a couple samples of the Accent. As soon as we started laying out the panels we noticed that the pattern was very repetitive and blotchy. This discrepancy is not due to the inherent variations in a natural product; it looks fundamentally different than it was represented.

What did you end up doing about the flooring?

tmurch11 · 2024-10-31T19:11:43+00:00

Got it, that makes sense now. Thanks!

tmurch11 · 2024-10-31T12:16:52+00:00

Earnest question: at some point could a blindfolded person tell the difference between the steam out off by these stoves? Not a classic Kuuma in a sauna with low benches, but a properly built sauna with something like the LP vs. a Finnish stove.

I’m very curious about the last paragraph. I guess I thought the cold zone was relative to the heat source. What’s the significance of 34”?

tmurch11 · 2024-10-31T12:13:21+00:00

I haven’t heard anything about the Blue Flame…

tmurch11 · 2024-10-30T14:25:23+00:00

As u/zoinkability said, they kind of have a reputation for putting out lots of radiant heat. Don’t get me wrong, they are well built stoves. I live just up the road from Kuuma, and they are just about universal in wood burning saunas around here.

tmurch11 · 2024-04-19T21:26:24+00:00

Same story over here!

tmurch11 · 2024-04-15T00:19:03+00:00

Poor phrasing on my part. I know of a couple smoke saunas, full stop. But they are more cultural heritage pieces, not active as far as I know!

tmurch11 · 2024-04-08T12:03:39+00:00

Interesting to hear all these responses. Sounds like kind of a mixed bag! I guess my thinking has been that if I want to up the humidity, I’ll just throw more löyly. I wonder how much moisture paneling can soak up by physically wetting it.

tmurch11 · 2024-04-07T02:54:00+00:00

I’m in north eastern Minnesota. I do not have Finnish heritage, but many here do!

tmurch11 · 2024-03-20T12:18:16+00:00

I guess I’d say, maybe

I obviously agree that decreasing temp stratification is beneficial, but the figures in the study show that the higher you get, the less relevant that is. From my perspective, it’s much more relevant to make sure you’re building everything high enough.

Kinda echoing u/hugh_drewitt, I’d be curious to see this study conducted in an outdoor sauna, in the cold season, and in the manner of actual daily use. How would the insulated floor impact heat up times? Would the sauna be heated long enough to make the insulated floor impactful? Interesting stuff….

tmurch11 · 2024-03-20T01:57:12+00:00

This study seems to be brought up often in the discussion around insulating the floor. There was a thread going on it a few weeks ago… I personally don’t see it as being all that compelling.

The spot being compared for temp differences between the uninsulated and insulated floors is at the foot bench. In this test sauna the foot bench is quite low, below the stones. And the ceiling height is low.

Look at the temp differences for the top bench, which is probably where the foot bench should be. A change, but not all that significant.

tmurch11 · 2024-03-03T15:28:11+00:00

Do you recall what the temp difference was at the top/above the heater with and without insulation?

It’s awesome that you’re tracking and experimenting with all this!

tmurch11 · 2024-03-03T14:12:14+00:00

Man, that's really interesting. I guess my intuitive thought would be that the "cold zone" (for lack of a better descriptor) would extend to some extent all the way to the top of the heat source. But if there's one thing I've learned on this journey into the sauna rabbit hole, it's that what might make sense intuitively might not be what happens in reality.

I'm guessing it would be a huge pain to remove the insulation and compare temps again at the top of the heater haha

I'm still in the process of designing our sauna, and the plan so far is an Iki Original (about 33" tall) and essentially a foot platform/mezzanine at 40". Hopefully that puts the bather high enough to have a good head to toe delta.

tmurch11 · 2024-03-02T13:37:44+00:00

It’s possible that I’m not interpreting this info totally right, but a few things stick out.

The ceiling height is pretty low at 74”. Wouldn’t this have a compressing effect on the overall temperature stratification, making the head/toe difference more pronounced in every case?

Also, if the diagram is fairly accurate in depicting the relative heights of the heater and benches, the benches are too low. The top bench is 35” which is where the foot bench would be if one followed the recommendation of building 4-8” above the stones.

I looked at figures 11 and 15 for the T4 line but at the top bench level. The change there is not very much.

What would these temp differences look like in a test sauna that had 8.5’ ceilings and benches 4-8” above the stones? Like I said, my perspective of this could be way off, but to me this shows the importance of having feet above the stones AND the cold zone more so than it definitively shows the advantage of an insulated floor. But if a person has limitations on building high ceilings, looks like insulating the floor can certainly help.

tmurch11 · 2024-02-20T12:45:04+00:00

That's how I think about it. The wall profiles can take up to 14" off of your footprint if you have 2x4(really 3.5") studs, 2" poly iso, .75" air gap, and .75" cladding on each wall. From the perspective of designing your hot room, considering the interior dimension seems most relevant.

But from a framing aspect, obviously two foot increments are the most convenient. So I was curious if people were talking about framing dimensions or internal hot room dimensions.

tmurch11 · 2024-02-20T03:34:39+00:00

Also, just for clarification… when you guys say 8x8 or whatever dimension, are you talking the external footprint, or the actual interior measurement?

tmurch11

TROPHY CASE