Choosing to post here instead of in the sauna thread.
I have read a bit about different schools when it comes to saunas. Some say you should use insulation/plastic/aluminum foil and some go without certain parts. But since the sauna in 9 out of 10 cases is in the bathroom, shouldn't there be a requirement for the same moisture barrier behind the surface in the sauna as in the rest of the bathroom? Why is there a requirement for a moisture barrier at the bathroom door, 4 meters from the shower but not in the sauna?
I know that many consider the sauna the driest room in the house, but that's when it's used, when it's not used it's like any other part of the bathroom.
Is there something I've missed or?
I have read a bit about different schools when it comes to saunas. Some say you should use insulation/plastic/aluminum foil and some go without certain parts. But since the sauna in 9 out of 10 cases is in the bathroom, shouldn't there be a requirement for the same moisture barrier behind the surface in the sauna as in the rest of the bathroom? Why is there a requirement for a moisture barrier at the bathroom door, 4 meters from the shower but not in the sauna?
I know that many consider the sauna the driest room in the house, but that's when it's used, when it's not used it's like any other part of the bathroom.
Is there something I've missed or?
I thought so too, but apparently that's not the case. The moisture that settles on the walls and floor apparently has time to dry out while the sauna cools down.
The rules for bathrooms are, in some cases, quite silly.
For saunas, there are hardly any rules. I built mine with a waterproof layer on the floor and up the sides (about 10 cm), then there's foil, then battens, and after that, horizontal paneling. I don't believe for a second that it would be hermetically sealed, nor is it likely intended to be.
If, however, there is foil, it prevents moisture from moving outward in the construction, which should be quite clear, I think. BUT if you then have foil somewhere outside of this, you create a zone where at least construction moisture has nowhere to go.
I built my sauna as a room within a room, where the sauna's insulation has an air gap against the house's outer wall, and this gap is also (slightly) ventilated.
It's pretty obvious that I should make the floor waterproof, so I can rinse with the shower and the water and any dirt will come back out (I do not have a floor drain in the sauna).
When the last scoop has been thrown, the humidity will only decrease, and at least my sauna heater emits heat until the next morning, so it should dry out quite well.
Whether foil is suitable or not, I leave unsaid, I did NOT put it on the wall against the bathroom but on all others + the ceiling. Nonetheless, I think continuous ventilation is many times more important.
For saunas, there are hardly any rules. I built mine with a waterproof layer on the floor and up the sides (about 10 cm), then there's foil, then battens, and after that, horizontal paneling. I don't believe for a second that it would be hermetically sealed, nor is it likely intended to be.
If, however, there is foil, it prevents moisture from moving outward in the construction, which should be quite clear, I think. BUT if you then have foil somewhere outside of this, you create a zone where at least construction moisture has nowhere to go.
I built my sauna as a room within a room, where the sauna's insulation has an air gap against the house's outer wall, and this gap is also (slightly) ventilated.
It's pretty obvious that I should make the floor waterproof, so I can rinse with the shower and the water and any dirt will come back out (I do not have a floor drain in the sauna).
When the last scoop has been thrown, the humidity will only decrease, and at least my sauna heater emits heat until the next morning, so it should dry out quite well.
Whether foil is suitable or not, I leave unsaid, I did NOT put it on the wall against the bathroom but on all others + the ceiling. Nonetheless, I think continuous ventilation is many times more important.
But if the sauna foil is not perfectly sealed against the waterproof membrane and other parts of the bathroom, moisture will still be able to get into the structure. This is obviously also the case if one chooses to forgo the foil.
Is it the case that the waterproof membranes for wet rooms can't handle the temperatures that occur in a sauna? It seems like it should also be addressed in the BKR regarding how to approach it when it comes to a sauna.
Is it the case that the waterproof membranes for wet rooms can't handle the temperatures that occur in a sauna? It seems like it should also be addressed in the BKR regarding how to approach it when it comes to a sauna.
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No, they are probably not intended for temperatures over 100°C. Down by the floor (as in my case), it's hardly over 40°C, so it should manage just as well as in the bathroom.
Normally, you don't shower in the sauna, and the water exposure is low compared to a wall you shower against.
BKR only applies if you tile the sauna; if you have wood, it might be NTR that's applicable, what do I know
Normally, you don't shower in the sauna, and the water exposure is low compared to a wall you shower against.
BKR only applies if you tile the sauna; if you have wood, it might be NTR that's applicable, what do I know
Even the water splashing is low against the wall at the door...
And many saunas do have tiles and presumably also "sealant" behind.
I can't access GVK's pdf, so I can't check what it says there, but under "questions and answers" on their site, there is this text:
"Do you have to have a waterproofing layer in the entire wet room?
Answer: Generally, the whole wet room is considered a risk zone, which is why GVK recommends having a waterproofing layer in the entire area. In very large bathrooms, spa areas, and the like, it may be warranted to consider which parts of the room will be exposed to water spraying, splashes, and potentially leaking water. If you do not apply a waterproofing layer throughout the area, you should follow the National Board of Housing, Building and Planning's Building Regulations and seal risk areas. Normally, the entire floor should have a waterproofing layer. Possibly, parts of the wall not exposed to water can be an exception. In areas with a risk of incoming moisture, an investigation should be conducted on where the waterproofing should be located to avoid a disaster."
You apparently don't need a waterproofing layer in the entire room if you opt out of tiles and "seal" according to the National Board of Housing, Building and Planning's regulations.
I feel like everything contradicts itself all the time. If I have tiles on a wall 5 meters from the wet zone, I need a waterproofing layer, but if I use some other material, it's apparently not as critical and just needs to be "sealed." And in the sauna, you can apparently even skip all waterproofing altogether...
And many saunas do have tiles and presumably also "sealant" behind.
I can't access GVK's pdf, so I can't check what it says there, but under "questions and answers" on their site, there is this text:
"Do you have to have a waterproofing layer in the entire wet room?
Answer: Generally, the whole wet room is considered a risk zone, which is why GVK recommends having a waterproofing layer in the entire area. In very large bathrooms, spa areas, and the like, it may be warranted to consider which parts of the room will be exposed to water spraying, splashes, and potentially leaking water. If you do not apply a waterproofing layer throughout the area, you should follow the National Board of Housing, Building and Planning's Building Regulations and seal risk areas. Normally, the entire floor should have a waterproofing layer. Possibly, parts of the wall not exposed to water can be an exception. In areas with a risk of incoming moisture, an investigation should be conducted on where the waterproofing should be located to avoid a disaster."
You apparently don't need a waterproofing layer in the entire room if you opt out of tiles and "seal" according to the National Board of Housing, Building and Planning's regulations.
I feel like everything contradicts itself all the time. If I have tiles on a wall 5 meters from the wet zone, I need a waterproofing layer, but if I use some other material, it's apparently not as critical and just needs to be "sealed." And in the sauna, you can apparently even skip all waterproofing altogether...
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