Hello everyone,
I have already read and searched around a bit here, but I am still not quite sure.
We are planning to build a house. It will be a semi-detached house. We have been offered a house with 36.5cm (14 inches) aerated concrete exterior walls without additional insulation. The interior walls are also planned to be made of aerated concrete. Soundproofing boards are to be installed between the wall and the neighboring house.
I have to admit that I am quite a layperson and am slowly working my way through the very conflicting statements and information. We don’t want to build a passive house, but it should be future-proof and reasonably designed. Overall, I would like to aim for a kfw70 house, but that is not solely about insulation...
I have read various information about aerated concrete, clay blocks (Poroton), and also about prefabricated walls. I find it interesting that the U-value of the prefabricated walls is apparently significantly better than that of comparable solid walls (without additional insulation). However, I can’t really grasp what a difference of 0.1 W/(m²K) actually means in reality... I lack the practical understanding of this.
What I think I know:
- Aerated concrete can be installed without additional insulation. But is it any good!? Does it only just meet legal requirements, or is it also sensible to build this way?
- Aerated concrete has poorer sound insulation compared to sand-lime brick or clay blocks. This could be a problem especially for thin interior walls.
- Regardless of what I build (even without extra insulation), a controlled mechanical ventilation system is highly recommended because the houses are very airtight.
- Aerated concrete has poor thermal insulation properties in summer (I still don’t understand why a material supposedly insulates well in one direction – during winter – but not in the other – summer –?!).
- I have often read that the costs of adding extra insulation to a wall do not pay off over a reasonable period (in terms of heating savings – of course this also depends on the heating technology).
Could you help me clarify where I might be wrong? Why is sand-lime brick usually recommended for interior walls instead of aerated concrete? Soundproofing? Less crumbling when drilling? Price?
On the website of the well-known aerated concrete manufacturer, I read that they also achieve low U-values (below 0.2). But these blocks are then less stable, significantly more expensive, and worse in sound insulation... So can you really generalize about aerated concrete or do you need to specify the exact type of block? My supplier only talks about 36.5cm (14 inches) blocks. So I don’t really know which will actually be used... I should probably ask.
Is omitting additional insulation really the “state of the art” and reasonable (does it not pay off in heating costs) or just cheap?
As I said, I don’t want to build a passive house but an economically sensible concept.
Which wall structure would you recommend and why under the above conditions?
Thank you!
I have already read and searched around a bit here, but I am still not quite sure.
We are planning to build a house. It will be a semi-detached house. We have been offered a house with 36.5cm (14 inches) aerated concrete exterior walls without additional insulation. The interior walls are also planned to be made of aerated concrete. Soundproofing boards are to be installed between the wall and the neighboring house.
I have to admit that I am quite a layperson and am slowly working my way through the very conflicting statements and information. We don’t want to build a passive house, but it should be future-proof and reasonably designed. Overall, I would like to aim for a kfw70 house, but that is not solely about insulation...
I have read various information about aerated concrete, clay blocks (Poroton), and also about prefabricated walls. I find it interesting that the U-value of the prefabricated walls is apparently significantly better than that of comparable solid walls (without additional insulation). However, I can’t really grasp what a difference of 0.1 W/(m²K) actually means in reality... I lack the practical understanding of this.
What I think I know:
- Aerated concrete can be installed without additional insulation. But is it any good!? Does it only just meet legal requirements, or is it also sensible to build this way?
- Aerated concrete has poorer sound insulation compared to sand-lime brick or clay blocks. This could be a problem especially for thin interior walls.
- Regardless of what I build (even without extra insulation), a controlled mechanical ventilation system is highly recommended because the houses are very airtight.
- Aerated concrete has poor thermal insulation properties in summer (I still don’t understand why a material supposedly insulates well in one direction – during winter – but not in the other – summer –?!).
- I have often read that the costs of adding extra insulation to a wall do not pay off over a reasonable period (in terms of heating savings – of course this also depends on the heating technology).
Could you help me clarify where I might be wrong? Why is sand-lime brick usually recommended for interior walls instead of aerated concrete? Soundproofing? Less crumbling when drilling? Price?
On the website of the well-known aerated concrete manufacturer, I read that they also achieve low U-values (below 0.2). But these blocks are then less stable, significantly more expensive, and worse in sound insulation... So can you really generalize about aerated concrete or do you need to specify the exact type of block? My supplier only talks about 36.5cm (14 inches) blocks. So I don’t really know which will actually be used... I should probably ask.
Is omitting additional insulation really the “state of the art” and reasonable (does it not pay off in heating costs) or just cheap?
As I said, I don’t want to build a passive house but an economically sensible concept.
Which wall structure would you recommend and why under the above conditions?
Thank you!
H
Hausqualle23 Jul 2015 12:06Schrimp schrieb:
I just think that Poroton or aerated concrete doesn’t make much difference. .. but there are significant differences between aerated concrete and Poroton ..B
Bauexperte23 Jul 2015 12:09Hausqualle schrieb:
.. there are huge differences between aerated concrete and fired clay blocks .. In my opinion, regarding the stated thesis, there is only one difference: one crumbles white, the other red.
Regards, Bauexperte
In our house, the interior walls have a different structural strength compared to the exterior walls.
While the exterior walls are optimized for thermal performance and therefore lighter, the interior walls are somewhat stronger.
The only somewhat challenging part for us was the bolt-supported stair railing. Special core drills had to be made there, which were then filled with concrete.
If 11cm (4.3 inches) walls are an issue, you can simply go with 17cm (6.7 inches) walls. This, of course, reduces the usable room volume.
While the exterior walls are optimized for thermal performance and therefore lighter, the interior walls are somewhat stronger.
The only somewhat challenging part for us was the bolt-supported stair railing. Special core drills had to be made there, which were then filled with concrete.
If 11cm (4.3 inches) walls are an issue, you can simply go with 17cm (6.7 inches) walls. This, of course, reduces the usable room volume.
H
Hausqualle23 Jul 2015 12:17Bauexperte schrieb:
Regarding the stated thesis, in my opinion there is only one: on one side it crumbles white, on the other red.
Regards, Bauexperte ... oh well ... your "expertise" is really quite interestingSimilar topics