Y-Tong (aerated concrete) - quality building material? (sound insulation!)

Ask your construction company which material is being used exactly and read the data sheet. This then has to be related to the noise levels at the construction site. On a busy main road, even calcium silicate brick alone won't help; you also have to optimize the windows (and not open them). In the dead-end street of a quiet residential area, however, you can live with anything...

We have another meeting tomorrow and are following up. After I read your answers to my wife, she, like me, now tends to prefer sand-lime brick. Two more questions for you, so we can sleep well: 1) Is the KS + ETICS option significantly more expensive or not? 2) Exterior Ytong 36.5 and interior KS: is this option still under consideration?

outside Ytong, inside KS doesn't help much against street noise. KS plus ETICS is more expensive. How much does the builder tell you. It is one more work step, and it also takes longer to build, since Ytong is particularly quick to build up. Labor costs!

There are Ytong blocks with an increased sound insulation value. Ask the building materials dealer or developer you trust. Alternatively, there are also aerated concrete manufacturers who offer a combined block: Outside 125 mm aerated concrete Middle 100 mm rigid foam core insulation Inside 175 mm aerated concrete This in one block.

Just spoke with Ytong. It was a professional consultation. The recommendation was (without knowing the situation on site exactly, so with reservation) still a Ytong 36.5 PP2 0.35 / 0.009. I was told that especially the windows must be very well soundproofed, because otherwise even the best limestone sand brick wall won’t help – especially in a two-story city villa with large window areas.

In addition, with limestone sand brick there is a high risk that the thermal insulation composite system (WDVS) will increase the noise again, and you won’t really benefit from the limestone sand brick. Therefore, we should stick to the 36.5 Ytong, choose good soundproof windows, and especially consider a Ytong solid roof, because it is often overlooked how noisy a wooden construction roof can be.

A facing construction made of wood or similar on the house wall facing the paved street is also conceivable, according to the advisor.

We will measure the sound levels over the weekend and see. Ytong also recommended this to us, because only the real environmental values provide information about the required soundproofing.

What I have learned so far: Unfortunately, sound protection and thermal insulation do not go together.

Outside 125 mm aerated concrete
Middle 100 mm rigid foam core insulation
Inside 175 mm aerated concrete. This all in one block.

And here the sound is significantly better then?

There are Ytong blocks with an increased sound insulation value. Ask the building materials dealer or developer you trust.

Alternatively, there are also aerated concrete manufacturers who offer a combined block:
Outside 125 mm aerated concrete
Middle 100 mm rigid foam core insulation
Inside 175 mm aerated concrete

This all in one block.

Although that sounds more like an improvement in insulation rather than soundproofing…?

Just spoke with Ytong on the phone. It was a professional consultation. The recommendation was (without knowing the situation on site exactly, therefore subject to reservation) still a Ytong 36.5 PP2 0.35 / 0.009.[…]

So Ytong recommends Ytong?