Hello everyone,
I often read about the concept of "breathing walls."
Statements like:
- "We were told not to insulate because otherwise my 31cm (12 inch) brick wall won’t be able to breathe anymore."
- "We don’t need a ventilation system; the timber frame wall has no membrane, so it can breathe well."
- "We have a vapor-permeable wall, so moisture can escape outside, and I don’t need a ventilation system."
- "The wall is vapor-permeable, a ventilation system is not necessary, and you basically don’t need to ventilate."
I keep seeing these and similar sentences online and have even heard them personally from house building companies—the latest just this Monday. Other opinions include: Don’t put photovoltaics on the roof due to too much electromagnetic pollution. He would never install a ventilation system. Climate change? That doesn’t even exist. At some point, I just got up and left.
I’m an engineer, not involved in house building. But in my opinion, these statements make no sense at all.
A wall can never really "breathe" properly.
Here, "breathing" means a significant moisture exchange.
How is this supposed to work physically? It’s not a thin membrane, but a thick, solid wall or one filled with insulation.
Sure, a certain amount of moisture transfer always occurs. But in my view, this is absolutely negligible. There is no way that the few liters of moisture produced daily in a single-family house could pass through the wall to the outside without either a ventilation system or manual ventilation. Physically, this just can’t happen.
Of course, it’s different with older houses. They have numerous leaks that allow air and moisture exchange. But modern houses are sealed tightly. Therefore, there is no real air exchange through the walls.
And beyond the aspect of "removing moisture to the outside," there is also the aspect of "bringing fresh air into the house."
My point is not to argue for or against ventilation systems. I am in favor, but it can also work without one if you don’t want it—just with regular manual airing, in my opinion.
What do you think? Do these "breathing walls" really exist?
Am I completely wrong? Or is this myth just incredibly persistent among home builders and even building companies?
Best regards,
Specki
I often read about the concept of "breathing walls."
Statements like:
- "We were told not to insulate because otherwise my 31cm (12 inch) brick wall won’t be able to breathe anymore."
- "We don’t need a ventilation system; the timber frame wall has no membrane, so it can breathe well."
- "We have a vapor-permeable wall, so moisture can escape outside, and I don’t need a ventilation system."
- "The wall is vapor-permeable, a ventilation system is not necessary, and you basically don’t need to ventilate."
I keep seeing these and similar sentences online and have even heard them personally from house building companies—the latest just this Monday. Other opinions include: Don’t put photovoltaics on the roof due to too much electromagnetic pollution. He would never install a ventilation system. Climate change? That doesn’t even exist. At some point, I just got up and left.
I’m an engineer, not involved in house building. But in my opinion, these statements make no sense at all.
A wall can never really "breathe" properly.
Here, "breathing" means a significant moisture exchange.
How is this supposed to work physically? It’s not a thin membrane, but a thick, solid wall or one filled with insulation.
Sure, a certain amount of moisture transfer always occurs. But in my view, this is absolutely negligible. There is no way that the few liters of moisture produced daily in a single-family house could pass through the wall to the outside without either a ventilation system or manual ventilation. Physically, this just can’t happen.
Of course, it’s different with older houses. They have numerous leaks that allow air and moisture exchange. But modern houses are sealed tightly. Therefore, there is no real air exchange through the walls.
And beyond the aspect of "removing moisture to the outside," there is also the aspect of "bringing fresh air into the house."
My point is not to argue for or against ventilation systems. I am in favor, but it can also work without one if you don’t want it—just with regular manual airing, in my opinion.
What do you think? Do these "breathing walls" really exist?
Am I completely wrong? Or is this myth just incredibly persistent among home builders and even building companies?
Best regards,
Specki
N
nordanney6 Mar 2020 16:49ypg schrieb:
Do you know what that means now? Yep, I’ve already received one for another quote.
The funny thing is, I posted the text a second time (quoted the text from @fragg and noted that I reposted it without links and that the old post can be deleted since I can’t do it myself). However, that post was deleted. Strange admin...
But I can live with a warning
H
hampshire7 Mar 2020 20:30nordanney schrieb:
I can live with a reprimand just fine There are people who happily live on Rügen.S
SoiCowboy25 Nov 2020 22:29I’m glad to have my CO2 monitor in the solid wood block house.
It reminds me every day when it’s time to ventilate.
However, the bathroom mirror has never steamed up, no matter how long or hot the shower is.
It reminds me every day when it’s time to ventilate.
However, the bathroom mirror has never steamed up, no matter how long or hot the shower is.
Specki schrieb:
I keep seeing these and similar sentences on the internetYes, you have to be careful with this internet. Sometimes nonsense is written there. :pS
SoiCowboy26 Nov 2020 00:01SoiCowboy schrieb:
I’m glad to have my CO2 meter in the solid wood block house.
It reminds me every day that it’s time to air out the rooms.
However, the bathroom mirror has never fogged up, no matter how long or hot the showers are. But I never expected it to be different. I prefer active ventilation.
H
hampshire26 Nov 2020 21:54Of course, walls cannot breathe. However, it is generally undisputed that different wall constructions can have an impact on the comfort inside residential buildings. If you take the term "breathing" as a metaphor, you can—if you wish—understand the core idea in a figurative sense.
Similar topics