Strength of the exterior wall

For us, a 36.5 cm exterior wall with aerated concrete blocks was standard. Other solid builders had also recommended and advised us of this in advance.

For a 24cm thick aerated concrete exterior wall, a U-value of approximately 0.76 W/m²K is achieved, roughly three times the value required by the energy saving ordinance.

OK, did he also say something about the energy standard? I, as a construction layman, find the 24 cm wall without additional insulation a bit tight, as we were always told that without additional insulation you should use the 36.5 cm wall in aerated concrete... I'm really curious what our specialists think about this...

Hello everyone,

I am currently dealing with exactly the same topic and am also building with Town & Country.

The topic is somewhat older and the regulations have since changed, but maybe the topic can be brought up again because it is found quite quickly on Google.

In my building contract as well, only a 24cm aerated concrete wall is planned. The house is currently supposed to be built according to the Energy Saving Ordinance 2016 regulations. However, after some research, it also seems to me that 36.5 is actually standard and that 24cm is quite thin? Are there any further or more recent expert opinions or experience reports on this?

I would greatly appreciate your help,

Regards Christian

There has already been a thread about this:

I also can't imagine a 24cm aerated concrete wall. My garage already has that plus 14cm mineral wool between the rafters...

In the basic contract of Town & Country, we only had 24 cm walls, but then switched to 30 cm. Otherwise, I think the energy saving ordinance requirements cannot be met, and I would take at least 30 cm purely for energy and sound insulation reasons!

However, we are completely satisfied with 30 cm walls; whether 36.5 cm then provides a significant added value I cannot assess.