Build your own sauna with a sloping roof - suggestions/notes/plans

Must I pay attention to anything when heating up for the first time?

Use your nose, if it smells strange, air out. There may be dust, dirt, or chemicals on surfaces that need to evaporate once. If the nose gives the okay, it is good

Already a great thing, having your own sauna :D

I started heating up yesterday afternoon, slowly from 40° to 80°, all without a vaporizer and without pouring water on the stones. At first there were still some strange smells, but that’s why I started heating up early. In the evening, there was no smell left.

The hygrometer showed about 40% humidity at room temperature before heating began. At 70%, it then dropped to below 0%... That seems a bit unrealistic to me?!

I want to test the vaporizer this weekend. Am I right in assuming that softened water from the "Bügelwasseranschluss" at the water softener for the heating system is the most sensible choice because of lime scale buildup?
Can anyone recommend a concentrate for pouring water on the stones?

Thanks!

I would top it up with wheat beer and bake some fresh rolls :D

Softened water is good for every device,
infusions we have numerous natural oils, order a small selection and test what suits you well in harmony with the light color and effect on mucous membranes, nose, throat, and breathing.
I will check later in our box.

We had a few such fragrances or oils from the drugstore. It is well known that many products usually achieve better results at Stiftung Warentest than any expensive specialty products. Ultimately, you can also try a little bit to see what creates your feel-good atmosphere. Weißbier would already be an interesting approach. You really can't do much wrong with that; I always think of the Scandinavians who tend to do everything rather rustic.
When it comes to water, I'm probably too simple-minded; I took it from the tap and there were no problems, but maybe you can also get it from the spring or something like that. I don't find that unreasonable at all, because especially in the sauna your own feeling is important and not necessarily research-based technical parameters; and feelings can't/must not always be explained.
This probably won't help you now, unless you invite us all so that we can test the sauna with 12 people; we would then start with the Weißbier infusion.

We do not accept ready-made infusions, only natural oils. A few drops in the infusion bucket with water, and in the bio sauna with a vaporizer a few drops in the small bowl