Soundproofing

[Rännil]

We are going to renovate one of the rooms in the house. It will become a children's room and is located wall-to-wall with the large bedroom on one side and the kitchen on the other. I'm now considering whether it's worth the effort to soundproof it.

The conditions are as follows:

• The room is 2.30X3.80 meters where the longer walls form the wall against the kitchen and bedroom.
• The existing construction is single gypsum, wooden studs (70 mm), single gypsum.
• On the kitchen side, it is tiled, and there are kitchen cabinets, as well as a fan, sink, stove, and dishwasher.
• On the bedroom side, there is partly a closet wall.
• The ceiling is tongue-and-groove pine panel that runs between the rooms.
• The floor is a cast concrete slab (basement underneath) + separate flooring has been cast in each room. Therefore, the walls are somewhat "cast-in." However, some type of paper was used against the walls during casting, so they are not fixed.
  
• Air inlet through the outer wall
• Light and sound-permeable door to the hall with a floor gap for airflow.

What I'm considering is tearing down the gypsum on the interior walls, filling with insulation, and then putting up a new gypsum board and sealing it to make it airtight. Possibly skipping tearing down the gypsum and instead adding double gypsum without insulating the interior walls.

I've learned that the wall should preferably be built in two layers with separated frameworks, but this type of construction isn't feasible due to the small room size, cost considerations, and not wanting to make it too complicated.

• Has anyone here on the forum experienced similar projects?
• Is it worth the effort to add insulation?
• Should I settle for double gypsum and sealing? The wall against the bedroom might be redone at a later stage, so there is an opportunity to improve with insulation from that side then.

 

[Tompafix]

We have 45mm walls. I did what they just described with the difference that I used OSB to stiffen the walls. Double gypsum is better from a soundproofing perspective. I noticed a clear difference in sound transmission afterward. The wall acted a bit like a resonance box before.