ᐅ Exterior wall construction material selection: aerated concrete, fiber insulation boards, mortar joints, and facing bricks (cladding)

Hello everyone,

We are currently planning our "urban villa" and have received the first offers. The masonry company proposed the following wall construction:

17.5 cm aerated concrete, 16 cm fiber insulation boards, 2 cm gap, and facing brick = 47 cm wall thickness.

At the same time, they mentioned a 30% higher cost estimate for masonry work if we choose sand-lime brick.

The construction would then likely be:
17.5 cm sand-lime brick, 20 cm fiber insulation, 2 cm gap, and facing brick = 51 cm wall thickness.

We are absolutely unable to decide between aerated concrete or sand-lime brick, excluding the additional costs.

Which option is "better" and more sensible?
We can’t really judge whether climate performance or sound insulation is more important, since we are currently living in an apartment with sloped ceilings.
Therefore, we don’t have experience with either and are looking for advice.
What do the experts or people familiar with both say?

Best regards

What is “better” and more practical?
What do the professionals say, or maybe people who know both options?

I have already explained this several times. You have been here for four years, so my Stone Mantra should be pretty familiar to you by now. That’s why I didn’t bother repeating it here. The match-up between white masons and red masons ends in a draw in the return leg just like in the first leg and has almost become a running joke on this topic here.

Using the search terms "11ant WDVS", "Mantra", "red masons", and "white masons" you should find everything I’ve ever said about this running joke (or FAQ) topic here;

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

Yes, I have, and my shell contractor offers both sand-lime brick and Ytong.

Some say that 17.5 cm (7 inches) Ytong is not solid enough and is far too thin, making it difficult to hang heavy cabinets. I don’t have Ytong here, so I can’t really understand what others mean by *bad* in this context.

Others say that if you want insulation, why choose Ytong at all—better to go with sand-lime brick.

I understand that everything has its advantages and disadvantages.

Specifically: Is a 17.5 cm (7 inches) Ytong exterior wall too thin? (Statically it’s fine, I know that.)

Should you choose the next thicker dimension here, or should you rather consider sand-lime brick straight away?

Mateo84 schrieb:

Specifically: is a 17.5cm ytong exterior wall too thin? (I understand that it is statically sufficient)

Should one choose the next thicker wall thickness here or rather consider moving towards calcium silicate blocks instead?

The brick facing already absorbs a significant amount of external noise. I would choose calcium silicate blocks—not for rational reasons, but as a personal preference for “solid construction.”

Both options will work well.

Installing Ytong blocks and cabinets is no problem for us; the bathroom vanity, the mirror cabinet, and the kitchen cabinets hold securely.

Sand-lime bricks absorb sound better. Will you be living in a quiet area? If it's like our location in a cul-de-sac with a 20 km/h (12 mph) speed limit, then it doesn’t matter. Sand-lime bricks will get more expensive, mark my words, mainly due to labor costs. Both building methods are solid enough to last a hundred years.

Nordlys schrieb:

Sand-lime bricks are becoming more expensive, probably due to labor costs.

Why? Use planned blocks. It’s like giant Lego bricks.