ᐅ Masonry – Construction Method for a Custom-Designed Single-Family Home

Yes, it will be more expensive. Sound sensitivity is also very subjective. In my opinion, you can never have too much.
I have Poroton solid masonry, but I am also familiar with aerated concrete. I do find that aerated concrete is somewhat more permeable to sound. I don’t live on a busy main road, but in a quiet residential area; still, I sometimes wish I had better sound insulation and don’t consider myself particularly sensitive.

A cavity wall construction probably costs an additional 30,000 to 50,000 euros (approximately 33,000 to 55,000 USD). At the time, I didn’t have the money for it (nor the knowledge).
However, if you are already building a cavity wall, adding more insulation and reinforcing the foundation shouldn’t cost that much more. You’d need to get a quote to be sure.

But yes, if the general contractor mainly uses aerated concrete (about 80%), it’s not easy to insist on a different type of brick, although aerated concrete specialists are usually also familiar with Kalksandstein (sand-lime bricks). White on white construction is often chosen, also for soundproofing reasons—because Kalksandstein is commonly used for interior walls.

Thank you very much for the numerous responses!

We have been offered the following wall construction:

• Interior plaster: Machine-applied gypsum plaster with quality level Q2
• Load-bearing masonry: 17.5 cm (7 inches) aerated concrete
• Insulation: 14.0 cm (5.5 inches) mineral wool insulation according to the thermal protection calculation
• Air gap: 2.0 cm (0.8 inches) ventilated cavity
• Facing masonry: 11.5 cm (4.5 inches) clinker brick in NF format

Our question now is: Is a 17.5 cm (7 inches) aerated concrete exterior wall structurally safe, provided it has been calculated and approved by a structural engineer?

Of course, we also like the monolithic construction method; however, overall it is considerably more expensive, especially when taking all additional costs into account. Furthermore, the monolithic method only achieves the KfW 55 standard, while the multilayer system described above enables the KfW 40 standard.

Ultimately, not only energy efficiency but also quality and structural safety are decisive for us. If there are solid arguments that justify the advantages of the monolithic construction, we would be willing to accept additional costs for it.

I look forward to further assessments and experience reports!

Sonar87 schrieb:

I am new here and would like to get your professional opinions and experiences on a specific topic. We are planning to build a custom-designed single-family house in the Bauhaus style and are currently deciding between two general contractors offering different construction methods:

• Option 1: Load-bearing masonry made of 17.5 cm (7 inches) aerated concrete, supplemented with mineral wool insulation, a ventilated cavity, and a facing brick outer wall.
• Option 2: Monolithic construction with 36.5 cm (14 inches) aerated concrete PPW2, also with a brick facade.

Use the weekend to get a little less new here and learn not only from what we write to you in your thread – it’s worth scrolling back and browsing around. Also look externally, for example where you can find "A house building roadmap for you too: the phase model of the HOAI!" It also explains "The Stone Mantra of 11ant." I see the following options:
Option U for unwise:
Only ask isolated questions here. Build your house design backwards, i.e., start with the given building composition and style. Commit yourself early on to building with a general contractor. Go to the companies you want to compare without prior consultation. Compare them using only two tools: an Excel spreadsheet and a public wildcard.
Option S for smart:
Get comprehensive advice, fill out the questionnaire here, and present your house design to the discussion field. Take a pause, leaving it to the outcome of the initial decisions to determine which construction method is the better choice in your particular case. Only develop the design to construction readiness then. Never go to a company without an advisor who is on your side (this can also be an independent architect, and I have mentioned some of my recommended colleagues here several times). Don’t lock yourself in from the start to building with a general contractor; instead, let general contractors only participate based on your tender. Be glad that the smarter way is at least not more expensive.

Tolentino schrieb:

But as for my personal preference, the ranking would be:
1. Cavity wall
2. Monolithic
3. ETICS (external thermal insulation composite system) or wood frame construction

My ranking would be:
A: Follow the Stone Mantra strictly
B: Vary the Stone Mantra, for example by using sand-lime brick or higher density/thickness aerated concrete instead of the aerated concrete variant mentioned
Z: Develop the planning starting from the wall builder’s perspective.
Whether ETICS, WDIS (external thermal insulation interior system) or monolithic (aerated concrete caliber 365 according to EH55/Building Energy Act, or probably caliber 425 for EH40), will result from this.

MachsSelbst schrieb:

I side with 11ant here and would go with what is common in the region and what the shell builders are proficient at.

I am not quite sure how closely you follow the creed of my school. I read here that the general contractor is not convinced by a (proposed by the architect?) wall assembly. It would be helpful to know what his two favorites and bestsellers actually are.

If this really means Bauhaus style and not "Hornbach style," many general contractors would be disqualified or the number of suitable candidates would be significantly reduced. Many general contractors hear "Bauhaus style" and think: "Sure, we can just arrange some shoeboxes with flat roofs, how hard can it be? – that’s just a roof left out, then insulation and a vapor barrier over the top floor slab." They also eat gnocchi, drink espressos, and drive Lamborghinis.

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https://www.instagram.com/11antgmxde/
https://www.linkedin.com/company/bauen-jetzt/

Sonar87 schrieb:

Now the question for us is: Is an exterior wall made of 17.5 cm (7 inch) aerated concrete structurally safe, provided it has been calculated and approved by a structural engineer?

From this, I understand that you have focused on the general contractor? Ultimately because of the price?

@ypg,

After extensive work with Excel and many months of careful analysis, we have identified numerous differences. During this process, we realized that we might not have given sufficient attention to the important topic of wall construction.

The overall concept is more cost-effective because it takes into account more points that are important to us. We have already focused on this, but have not yet signed any agreements. Therefore, we remain flexible and would like to take the opportunity to review it once more and make adjustments if necessary before any potential errors occur.

Since there are many differing opinions on this topic—as in almost every trade—I would like to hear your assessment once again.

Sonar87 schrieb:

After intensive work with Excel and many months of careful analysis, we identified numerous differences. During this process, we realized that we might not have paid enough attention to the important topic of wall construction.

On the contrary: too much, and done at the wrong stage of the process.

Sonar87 schrieb:

The overall concept is actually more cost-effective because more points important to us were taken into account.

What does that mean in English?

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https://www.instagram.com/11antgmxde/
https://www.linkedin.com/company/bauen-jetzt/