Build a sauna wall that is moisture-proof against the floor, how should I think?
nizzehult
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nizzehult
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I am planning to completely renovate a small bathroom and at the same time build a mini sauna there. The sauna will be partly built as a standalone but also utilize three of the room's existing walls. Since it is a very limited space (191x172), every cm is important, so I'm considering doing it this way and would like opinions if I'm thinking correctly.
For various reasons, I want to have a single tiled floor throughout the bathroom, and the idea is that I should be able to relatively easily remove the sauna in the future if needed. Therefore, I don't want to attach a base plate to the floorboard before casting leveling compound and laying tiles, which is otherwise the norm.
It's the fourth wall that I'm considering, the one I have to build myself and where the door will be located. The entire wall, which will be 191cm wide, will consist of 45x45 studs, so it won't be particularly complicated. It will be attached to the studs in the respective existing walls, so a few simple supports in inorganic material against the floor should suffice if you choose to place it a few cm above the floor, and then you can seal the gap underneath with practically anything, such as latex or silicone. Unless there's a better alternative, like a bottom rail of composite? The solution of sealing the gap with silicone feels a bit iffy...
I also don't plan to add any wall covering on this wall on either side; the panel mounted on battens with plastic behind it should suffice, mainly to save space. On the existing walls in the sauna itself, I will probably add a narrow strip of wall covering at the bottom, not wider than necessary to fold up the floor's waterproof membrane, and so that there's room to place a half or quarter tile there. Otherwise, no wall covering, just plastic directly on the studs, battens on that, and then the panel on the outermost layer. Also for space reasons.
Am I thinking correctly now? I have a pretty good grasp of the rules that apply to constructions in wet rooms.
For various reasons, I want to have a single tiled floor throughout the bathroom, and the idea is that I should be able to relatively easily remove the sauna in the future if needed. Therefore, I don't want to attach a base plate to the floorboard before casting leveling compound and laying tiles, which is otherwise the norm.
It's the fourth wall that I'm considering, the one I have to build myself and where the door will be located. The entire wall, which will be 191cm wide, will consist of 45x45 studs, so it won't be particularly complicated. It will be attached to the studs in the respective existing walls, so a few simple supports in inorganic material against the floor should suffice if you choose to place it a few cm above the floor, and then you can seal the gap underneath with practically anything, such as latex or silicone. Unless there's a better alternative, like a bottom rail of composite? The solution of sealing the gap with silicone feels a bit iffy...
I also don't plan to add any wall covering on this wall on either side; the panel mounted on battens with plastic behind it should suffice, mainly to save space. On the existing walls in the sauna itself, I will probably add a narrow strip of wall covering at the bottom, not wider than necessary to fold up the floor's waterproof membrane, and so that there's room to place a half or quarter tile there. Otherwise, no wall covering, just plastic directly on the studs, battens on that, and then the panel on the outermost layer. Also for space reasons.
Am I thinking correctly now? I have a pretty good grasp of the rules that apply to constructions in wet rooms.
nizzehult
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nizzehult
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In a sauna, you always have plastic. It works as a moisture barrier there. Then there is ventilation between the panel and the plastic because there are battens in between.
nizzehult
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nizzehult
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Steam. That's how you build a sauna. Period. Google it and see for yourself. So I have no problem with that. I've built a sauna before, but back then the house was new.
nizzehult
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nizzehult
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Ah, stop it with the amateur theories. Read here instead:
https://www.dinbyggare.se/bygga-bastu-sa-har-bygger-du-en-bastu-i-losvirke/
https://www.dinbyggare.se/bygga-bastu-sa-har-bygger-du-en-bastu-i-losvirke/
nizzehult
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nizzehult
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Foil and plastic are the same thing
If I remember correctly, saunas have been built for over 100 years without either plastic or foil, and I can't find reports of major moisture or water damage to these, can you? Due to vile recommendations and made-up industry rules (to sell junk), all sorts of nonsense are recommended nowadays! And people like you follow thoughtlessly like a lost sheep without making your own analysis! Your bathroom renovation wasn't exactly impressive, to say the least. Good luck and have a nice weekend!
No need to seal any gap underneath, heat rises. We had a freestanding sauna in the laundry room, one of those you buy pre-made from Tylö and set up, it stood on adjustable feet, and there was a gap of about 5 cm to the floor. You usually have a vent in the wall at the bottom of a sauna, and it does the same thing as a gap underneath. Many years later, I took it apart, rebuilt it on the plot, put a roof on, and it became a playhouse for the kids. I didn't see any plastic, it was just sauna paneling and gullfiber.
nizzehult
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But what is it that you don't understand? A sauna emits a lot of humid steam that, if not shielded in some way, gets absorbed by wall studs and other areas where you definitely don't want moisture.
Then, it's one thing to build a completely detached sauna in the yard (or for that matter: in a bathroom), where plastic is not a concern in the walls you set up. But in the middle of the house, you don't want moisture to spread in any way to adjacent rooms or studs. It's the same principle when applying waterproofing in a bathroom; it's just that here the plastic forms the waterproofing layer. Insurance companies, along with other bodies, have agreed on a set of rules that must be followed for you to receive compensation. Of course, you can do like @Jonatan79 and go your own way, thinking your own rules are sufficient, but it will come back to bite you when you try to sell the property or when damage occurs.
Of course, the heat rises upwards, but the incoming airflow (ventilation) shouldn't be too large, or the whole sauna will cool down too quickly. It's common to place an outlet right under the heater, nothing more. A gap along the entire wall is too much.
In my previous house, I also built a sauna in a space that can best be described as a large closet adjacent to the bathroom. I asked the carpenters who put the house together how I should proceed and how they would have done it, and it was exactly as I plan to do here: plastic on the wall, battens on the studs, and then paneling on top. So, this is not something I came up with myself. The only major difference is that there were gypsum walls, but here I will not have any wall cladding at all.
Then, it's one thing to build a completely detached sauna in the yard (or for that matter: in a bathroom), where plastic is not a concern in the walls you set up. But in the middle of the house, you don't want moisture to spread in any way to adjacent rooms or studs. It's the same principle when applying waterproofing in a bathroom; it's just that here the plastic forms the waterproofing layer. Insurance companies, along with other bodies, have agreed on a set of rules that must be followed for you to receive compensation. Of course, you can do like @Jonatan79 and go your own way, thinking your own rules are sufficient, but it will come back to bite you when you try to sell the property or when damage occurs.
Of course, the heat rises upwards, but the incoming airflow (ventilation) shouldn't be too large, or the whole sauna will cool down too quickly. It's common to place an outlet right under the heater, nothing more. A gap along the entire wall is too much.
In my previous house, I also built a sauna in a space that can best be described as a large closet adjacent to the bathroom. I asked the carpenters who put the house together how I should proceed and how they would have done it, and it was exactly as I plan to do here: plastic on the wall, battens on the studs, and then paneling on top. So, this is not something I came up with myself. The only major difference is that there were gypsum walls, but here I will not have any wall cladding at all.
nizzehult
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nizzehult
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Oh really, but try playing that card with the insurance company if you experience water damage!
- Why does the wet room lack waterproofing around the sauna?
- Oh, it's unnecessary because it dries so quickly anyway.
Note that this is a wet room and in such a room, there must - not should - be waterproofing on all walls and on the floor.
The alternative for me would have been to place the waterproofing on the studs and then build the sauna on these, the only difference being that in this case, the waterproofing consists of the plastic.
- Why does the wet room lack waterproofing around the sauna?
- Oh, it's unnecessary because it dries so quickly anyway.
Note that this is a wet room and in such a room, there must - not should - be waterproofing on all walls and on the floor.
The alternative for me would have been to place the waterproofing on the studs and then build the sauna on these, the only difference being that in this case, the waterproofing consists of the plastic.
Water damage in a wooden stud wall with Sauna panel that is also an interior wall?! Show me such an example and I will be surprised. Read some physics and think for yourself, maybe you will understand better. Then read up on why insurance companies and the construction industry scratch each other's backs and you'll understand even better…