Masonry for a two-family house

Hello,

we are a bit overwhelmed regarding the choice of the exterior masonry.

Basically, the choice is between Poroton (better sound insulation, absorbs less moisture) or aerated concrete (better thermal insulation).

What do you think about the options? It's about a two-family house with 220 sqm.

1. Poroton T 14 24 cm + [WDVS with 12cm rigid foam board WLG 035]
2. Poroton 36.5 without insulation T 10 U-value 0.25
3. 24 cm aerated concrete without insulation (doesn't work at all, right?)
4. 30 cm aerated concrete + €7,500
5. 36.5 cm aerated concrete + €12,000
6.

What makes sense?
Of course, a [WDVS] is cheaper than a monolithic wall structure.

Question of belief: my opinion: none of that, dear sand-lime brick plus ETICS. Best sound insulation, best statics, best thermal insulation combined alternatively double-layered.

Btw, for us aerated concrete was the cheapest (but definitely not an option for us), it varies greatly regionally.

Build with the system your construction company masters best. When executed cleanly, all systems are well suited for single-family houses and you won’t notice any difference living there.

3. 24 cm aerated concrete without insulation (that’s not an option, right?)

I can’t really imagine that it is still being offered.

4. 30 cm aerated concrete + €7,500
5. 36.5 cm aerated concrete + €12,000

Both are appealing to me, 4. for the Energy Saving Ordinance and 5. for KfW55. But, as I have already recommended several times,

Build with the system your construction company masters best. If executed cleanly, all systems are well suited for single-family houses and you won’t notice any difference while living there.

the most sensible advice would almost be to look for another builder if all the mentioned alternatives come from the same one.

If someone says, use stone X either purely for the Energy Saving Ordinance or with extras for KfW, that’s okay; but knowing stone X and stone Y equally well, I put a question mark behind that. That someone processes Bisotherm as well and gladly as KLB, I would believe. But Ytong or Poroton are too different from each other.

Typically, a builder belongs either to the red mason or white mason faction, rarely are they spotted as evolutionary or catholic/evangelical mixed.

Basically, as the client, I have the choice. Therefore, all companies would use both types of bricks.

Poroton or aerated concrete is basically the question.
Most companies we visited prefer Poroton because the sound insulation is too poor with aerated concrete.

Regarding 1. The company explained to us that it becomes cheaper with ETICS, among other things because of a smaller foundation slab. They preferably build with this system. But how is the sound insulation with a 24 cm brick? There is a street nearby us.

Regarding 2. Two companies build exclusively monolithically; however, these companies also have a higher base price.

Regarding 3. Franchise companies - claim that a 24 cm wall without insulation is sufficient, for which decentralized ventilation including is provided.
Thicker walls have the mentioned surcharges here.

Regarding 1. The company explained to us that it becomes cheaper with ETICS, among other things due to a smaller base slab.

The joke that the house could be significantly cheaper because of a 32 cm shorter and narrower base slab is a good one. I have to frame that.

But how is the sound insulation with a 24 cm brick? There is a road nearby for us.

Regarding sound insulation, one should not imagine a wall as a heavily armed crocodile that sound cannot get past, and that this alone is enough. Every newly built house initially has to deal with somewhat more sound, but this is not due to the evil aerated concrete but simply because at first no bushes provide diffusion of the sound from the road on its way to the house wall.

Regarding 3. Franchise company - Claims that a 24 cm wall without insulation is sufficient, but includes decentralized ventilation.

Franchise from whom or what? - 24 cm exterior walls ceased to be encountered in new buildings after the oil crisis of 1973 as far as I know. If that works, he should patent it. What magic additive is supposed to be in his brick?

The change from T14 to T9 would cost about €12,000 with the general contractor we are currently favoring. He mainly builds with ETICS. Would you spend this money?

The two general contractors who build with T9 accordingly have higher prices from the outset.

The other option would be to "tune" the wall of Town & Country for an additional charge, probably to 36.5 cm aerated concrete.