Insulate new construction 36.5 aerated concrete?

Args. It's about the renovation of facades... of course they are renovated, but not the ETICS itself (that was not touched...). Every plaster facade must be renovated regularly, but not the insulation behind it or the brick (both will outlive you if properly installed, both won't if done carelessly). And the stated 22 years is actually a really long time for a plaster facade....

And according to the study, damage patterns were even found more frequently on facades with a monolithic wall structure -> So here you have a higher probability of your renovation needs! So according to this study, you would even have a lower risk of future costs with an ETICS.

So I'm out and I take it like the people in the green forum. You can't be discussed with, you twist and turn, can't or don't want to understand.

In the publication I read, 22 years of damage-free time for ETICS and 35 years of damage-free time for mineral external plaster are assumed. The silicone resin plaster currently used on monolithic facades certainly has a significantly longer service life.

And the ETICS facades were regularly maintained to achieve these service lives. And these were not comparable in thickness to today's ETICS systems. Likewise, the 2mm plaster has certainly not always been that thin.

But now, completely independently of studies, just think logically. Walk through the city and you will see hundreds of ETICS renovation cases. And you see buildings 100 years old with original plaster.

Think logically: The monolithic wall is mechanically much more resilient, and if something happens, it is easy to repair. There are simply no thermal bridges, no moisture problems, etc. If the wall is 33cm instead of 36.5cm due to damage, it is simply repaired.

The monolithic wall has, as you noticed, fewer problems with algae. Fewer problems with woodpeckers.

Even if the ETICS facade is only 3% more susceptible to mechanical damage, moisture damage, etc. -> it is not worth it for a €10 per year cost difference for a 25% improvement.

Jan, we are talking about new construction. Please, why should a builder cover a 17.5 cm Ytong with Styrofoam and then plaster it, when for the same money or possibly less he can plaster the 36 cm stone without Styrofoam? Eggshell versus solid composite. That is the question we are facing. If it can be more expensive, then of course a 17.5 cm Ytong plus insulating wool plus clinker is the best. But that is too expensive for us. And it won’t get warmer inside, only easier to maintain. And please don’t come with any lab values. If I can heat 100 sqm for 600 euros a year and save 10 euros through the use of Styrofoam, it doesn’t matter.

And what about the settlement cracks in the plaster that you find on many monolithic walls? With the ETICS, you have less trouble with that (although there are also stories that the panels would shrink and thus could cause cracks later).

The profit lies in purchasing. But why should one repeat it, your calculation is clear anyway. So what. It is not about 10€ energy costs per year, completely irrelevant (as you yourself - only motivated differently - observe).

Our construction company would also work fully area-wide with fabric reinforcement on the aerated concrete exterior; this should make settlement cracks at least as unlikely as with an ETICS, I assume?

I came to my decision based on the advice of my brother, who is a master painter, has insulated thousands of apartment buildings with the Sto system, and professionally considers it not okay. I simply believe him when he says plastering is okay, but monolithic. The best would be a clinker brick construction. But we don't have the money, I am not far from retirement, and then I want to be debt-free. The repayment must not take longer than 2023.