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

So calling a sound reduction of 40dB "practically non-existent"... cool guy. Did he at least immediately find the right windows with >50dB sound insulation for you and tell you how much that fun will cost? A few thousand bucks can quickly go into that...

Your calculation is correct. Regarding the data: "Ytong Schallschutz" in Google image search, the first hit for me is directly a comparison table. Ytong 36.5 has 42dB, Silka 24 has 54dB.

We have now sampled soundproof windows of area III, and the seller also said that everything beyond that is absurd and eventually uneconomically expensive. He was of the opinion that the Ytong 36.5 is suitable in terms of sound insulation - given the relatively manageable 30 km/h one-way street, albeit cobblestone. The bedroom is in the completely opposite direction.

As I said, I am slowly going crazy. This is a weekly back and forth. Everyone says something different. It wouldn’t particularly bother me if I don’t have 15 dB in the kitchen when a car passes by, but rather 25-30.

The further away I am, the less sound there is, right? On the side facing the small street there would now only be the kitchen, guest WC, dressing room, and guest room.

We had now sampled soundproof windows of category III and the seller also said that anything further upwards is insane and eventually economically unviable. He was of the opinion that the Ytong 36.5 is adequate in terms of sound insulation - given the relatively quiet 30 km/h one-way street, although cobblestone. The bedroom is in the completely opposite direction.

As I said, I'm slowly going crazy. This is a weekly back and forth. Everyone says something different. It wouldn't particularly bother me if I didn't have 15 dB in the kitchen when a car passes by, but rather 25-30.

The farther away I am, the less the noise, right? On the side to the small street there would only be the kitchen, guest WC, dressing room, and guest room.

The seller's logic is exactly what I meant. 40 dB windows fit well if you build with Ytong. But slapping 40 dB windows (preferably floor-to-ceiling all around) into a 55 dB wall makes little sense. If the street is really that loud, you have to bite the bullet and really invest in the windows. Borrow a proper sound level meter and do some test measurements on the property.

I’m reminded of various builders who want to put 50 cm of Styrodur on their walls to squeeze out the last 3 cents of heating cost savings per year.

The seller’s logic is exactly what I meant. 40dB windows fit well when building with Ytong. But installing 40dB windows (ideally floor-to-ceiling all around) in a 55dB wall doesn’t make much sense. If the street is really that loud, you have to bite the bullet and accept it also with the windows. Just borrow a proper sound measuring device and do some test measurements on the property.

I am reminded of various builders who want to slap 50cm of Styrodur onto their walls to save the last 3 cents of heating costs per year.

I can also understand the logic; I prefer the monolithic way too, it’s somehow just more appealing.

It’s not about saving 3 cents on heating costs for us, I don’t care about that much, but I don’t want to sit in the house thinking: “Hmm, okay, yeah: the stone is pretty crap.” We only care about the sound – whether insulation is outside on the stone or inside the stone doesn’t really matter to me. The values are similar anyway and also high due to the energy saving regulations (maybe even too high), but that’s a different topic.

We’ll look into getting such a device! Thanks for the tips!

The further away I am, the lower the sound, right?

Yes, the sound pressure decreases with distance from the source. The perceived impression is not quite the same, because with greater distance there is also more in between for the sound to reflect off. In total, including the overtones, the noise can therefore still be perceived as more disturbing - but at least quieter.

So friends, I'm bumping this thread again. The other day, I measured the noise for 2 hours from 4-6 pm using a purchased app to get a somewhat clear insight. The app seems sensitive, as it could hear our whisper from 3 meters away. The measurement was taken on the current terrace at a wooden door that was built directly next to the noise source (the wooden door was ajar, phone with microphone facing the open side). The following values were recorded at a distance of about 10 meters from the source:

Average: 44 dB (from about 7200 seconds of measurements)
Background noise at about 34-37 dB outdoors
MAX: twice briefly 75 dB in two hours
Cars usually about 50-60 dB

In principle, the Ytong PP02 with 42 dB sound insulation and the windows of the SSK 3 should be sufficient, right? Bedrooms etc. are not on the noise side.

What do you think? Alternatively, I had already considered the PP4 (higher bulk density with 0.5), but with a worse U-value of 0.26 instead of 0.21.