Is it sufficient as sound insulation according to DIN4109 in a single-family house?

I just joined the Bauherren-Schutzbund and would commission an advisor from there.

They also check the contract if you want.

The inspection is at least as important as the contract. Unfortunately, anyone can call themselves a construction supervisor. Just like with brokers, there is a lot of malpractice. Better to hire a sworn expert and have every trade inspected.

Yes, thanks first of all for your input.

We got in touch with the construction supervisor because he "is on the property." He is also connected with the house building company that has already built many houses there with him. Until now, I didn't even know that construction supervisors exist. We still don't completely understand what all he does. In any case, he would always be on board.

Regardless, we will commission an expert through the Bauherren-Schutzbund. The construction supervisor seems reputable and is well rooted in the town, but he is not independent. I hope it doesn't alienate him if we get an expert at the same time, but we definitely want that.

I will have the Bauleistungsbeschreibung checked by the Bauherren-Schutzbund and see what he says about the topic of sound insulation.

Which sound insulation is important to you, the (1.) from outside the house, or (2.) inside?

1. This is actually taken care of by itself in a typical residential area and with windows that comply with the current energy saving ordinance. Otherwise, just build solid with Poroton or sand-lime brick (and ETICS) if there is increased demand here.

2. This mainly depends on habits and individual factors. For example, a very poorly sound-insulated house can still be quiet and vice versa: Where is the washing machine located (ground floor/upper floor), how quiet is the dishwasher? Are the TV internal speakers or a 1000W system used, are there sound-absorbing furnishings, staggered or identical working and sleeping times, and so on and so forth.

By the way: even the best sound insulation does not replace proper child upbringing. Some may even find it good to hear if things are getting a bit lively in the children's rooms. Or to hear that the shower is finally free. Don’t get me wrong, I’m also more in favor of quiet in the house...

Which sound insulation is important to you, the (1.) from outside the house, or (2.) inside?

1. This is actually taken care of by itself in a typical residential area location and windows that comply with the current energy saving regulations. Otherwise, just build solid with Poroton or sand-lime brick (and ETICS) if there is an increased need here.

Do not overlook that the insulation of even the best stone or window can be negated again by a decentralized ventilation system.

even the best soundproofing does not replace sensible child-rearing. Some might even find it good to hear if things are getting a bit wild in the children's rooms.

When it (here especially: the wall/furniture) gets too wild, there is usually nothing to hear at that moment. Dangerous silence and all :D