Which stone for exterior wall

I asked some general questions regarding wall construction. Should I unsubscribe just because I know a structural engineer?

Höösch or in plain language: keep calm. I think you should not be surprised by the suggestion to consult your structural engineer. You mention the proposal of 24 cm masonry but fail to provide its explanation. Instead, you only later reveal that a railway line runs near your property. How frequently is this railway line used? Once per hour, every 20 minutes, or more often? Regular passenger or freight traffic?

I simply assumed/claimed that the "thin" wall which is not calcium silicate stone plus insulation is the cheapest option because, in the construction specifications, the standard is listed as I understand it, and more is always possible at an extra cost.

We build purely monolithic with 36.5 cm masonry; are we therefore "outliers" because in the construction specifications available to you it says stone + ETICS? By the way, Ytong® PP, with a lambda value of 0.07 W/(mK) and thickness 36.5 cm, has one of the best insulation values among stones while still providing good load-bearing capacity. Again – there is no single “stone” for all construction projects! Every plot as well as the needs/wishes of the future occupants require individual consideration. If I were you – and I am definitely no fan of stone + insulation – I would move away from aerated concrete or Poroton and actually go for calcium silicate stone. Especially if a) the noise from the railway line proves to be quite high or b) I were very noise-sensitive. However, I would choose a different insulation instead of the much-praised ETICS. If the noise level is tolerable, you can stay with 17.5 cm hollow brick or aerated concrete + 16 cm insulation. What the pre-built brick may lack is compensated by the 16 cm insulation. Rhine regards

I am completely calm.

On the railway line, 6 passenger trains run per hour plus occasionally (also at night) a freight train.

You are not outliers (have read about the variant several times) but I would guess that 17.5 cm masonry + insulation is cheaper than 36.5 cm masonry? And that for this reason exactly 17.5 cm masonry + insulation is stated in the construction service description.

I also know that the stone does not exist. In general, it can be said that sound insulation plays a bigger role here than elsewhere.

The next question in connection with your suggestion would be how much worse 17.5 cm sand-lime brick + 16 cm insulation insulates than 17.5 cm aerated concrete + 16 cm insulation, or whether the insulation should be thicker than the original 16 cm when using sand-lime brick.

Regards

The insulation boards would be the same in both cases, and since the stone contributes almost nothing to the thermal insulation, the overall values would only differ negligibly.

Regarding costs, no exact information can be given because each provider somehow calculates differently. Basically, what sells well (= is bought a lot) costs less. For one person, that's aerated concrete, for another KS, and for yet another Poroton. By the way: With monolithic wall construction, you save the second work step, which is why it doesn’t necessarily have to be more expensive overall. However, there are other factors to consider...

In summary: Get concrete offers and question why exactly this is being offered to you. Then you can form your own opinion – or ask here again.

Best regards

K1300S

I am completely calm.

On the railway line, 6 passenger trains run per hour plus occasionally (also at night) a freight train.

That's already quite a lot; but you can talk in the garden, right?

... I would guess that 17.5 cm masonry + insulation is cheaper than 36.5 cm masonry? And that is why 17.5 cm masonry + insulation is stated in the construction service description.

No, not really. But it depends on the purchasing conditions of the respective supplier. If he signals — below the annual negotiations — to his supplier a quota of about 30 houses/coming year, made with aerated concrete, his purchasing conditions for sand-lime brick will certainly be worse than if he had agreed on the framework conditions for 30 houses/year.

The next question in connection with your suggestion would be how much worse 17.5 cm sand-lime brick + 16 cm insulation insulates compared to 17.5 cm aerated concrete + 16 cm insulation, or whether the insulation should be even thicker than the original 16 cm when using sand-lime brick.

That cannot be answered generally, precisely because the site-specific data are not known.

I would also postpone this decision to the time after the heat demand calculation in your place. When you know the energy demand of your new building, you can "calculate" with different stones/insulation thicknesses; even with thicknesses as long as the building application has not been submitted.

Edit: The latter, of course, only if your supplier can economically procure all possible stones or you are building with an architect.

Rhenish regards

That's quite a lot; but you can still have a conversation in the garden, right?

First of all, thanks to you!

The passenger trains are modern RB/RE that run on electricity and don’t make much noise or for long. They go slowly because the station is very close. So maybe each train is too loud to talk for about 5 seconds.

Only the freight trains make proper and longer noise.