Sound insulation; mid-terrace house on the street side, room-to-room construction method

Hello everyone!

We are currently in the process of moving the bedroom from the attic to the upper floor because the noise from the nearby street and the highway is sometimes very noticeable in the attic.

Since we live in a mid-terrace house, I want to insulate the wall to the neighbor as well as possible (sound insulation).

My approach: 95mm thick Sonorock acoustic panels will be laid on the floor with a gap to the walls. On top of that, chipboard panels will be laid, followed by impact sound insulation. On this newly constructed floor, new walls will be built in stud construction with drywall "Die Blaue" and again Sonorock acoustic material, so without contact to the old walls.

My questions: is this approach okay? Should I build a complete room-in-room structure, i.e., also suspend the ceiling? The room has a door and a window – should the room-in-room have a second door and a second window?

I look forward to your answers!

Morning!

So - I must have understood everything completely wrong.

Who is the soundproofing supposed to be for - for you or the neighbors?

The floor construction is, in my opinion, hair-raising - or at least very exclusive!

Best regards,
Tomtom.

Hello TomTom1, thanks for the answer!

The soundproofing is intended for us. Of course, it also blocks sound in the opposite direction - why not? But if the approach is completely wrong...

The floor structure is designed to block the sound coming through the (shared) floor slab.

Hello!

So, you should definitely get professional advice to build up some basic knowledge.

I don’t know anything about terraced single-family houses, but

- you won’t have a common floor slab on the upper floor
- if you do have a shared concrete ceiling (does fire protection allow that?), you won’t have a common screed at least
- sound is insulated through decoupling; a few millimeters are already enough and through mass; stone wool of this thickness on the floor is absolutely pointless.
- statically, that doesn’t work anyway, the studs have to be anchored in the screed or concrete floor
- very important: such a construction can cause you significant mold problems!! Read something about the dew point.
- since a window opens inward, a so-called box window will not be so easy to realize; a different glazing would be simpler, e.g. 6+3 and 4 mm.
- the thing with the door is the only easy part – we even have a tiny extra hallway in front of the bedroom.
- a suspended ceiling improves the room acoustics – will probably also bring some sound insulation (but with a concrete ceiling rather unnecessary).
- a measure that helps quite a lot and costs little: carpet. Laminate would be a clear step in the wrong direction.

So: don’t just start – plan properly first!

Best regards, Tomtom.

I have an on-site appointment with a drywall installer tomorrow, but I have already made some of my own considerations in advance!

So you mean it would be sufficient to equip the shared partition wall (38cm but really very thin-sounding without end!) with a drywall lining and to equip the floor with, say, 45mm Rockwool, chipboard, impact sound insulation, laminate (we have cats, full carpet is not possible) and a thick doormat?

I know that internal insulation of the exterior wall can be problematic – but in at most two years, exterior insulation will also be added. Alternatively, I have requested an offer for a new window: soundproof glass 37 dB with an attached roller blind to replace double glazing from 1992.

(Just to clarify again: I had imagined a completely decoupled room inside a room; and the profiles, the drywall boards, and the insulation are not so heavy that it would become a structural problem if everything rests on the floor construction, is it?)

Nachtrag When it comes to the "floor slab," you are of course right! But we have a common screed, as can be seen in the construction photos from 1952/1953... Nachtrag Ende

Hello!

No, it is not a question of weight. You cannot apply stone wool on the floor, place an OSB board on it, and mount walls on top!

And the screed cannot run through - unless the walls were built as you intended.

As for the risk of mold - I fear that with the external insulation (probably Styrofoam?) the situation will worsen.

37 dB are, if I recall correctly, not sound insulation (4 + 6 mm?), our "normal" windows had 34 dB. In the bedroom we had 44 or 45 dB - but that doesn’t help much if ventilation is not ensured otherwise.

A 38 cm wall should actually be sufficient - are wastewater pipes running inside the wall?

Best regards,
Tomtom.