Soundproofing damp? (threads amalgamated)

[Michaelsf90]

So I have never done plastering and am a complete novice. I'm looking at soundproofing a party wall. Building a stud wall an inch from the party wall to create a cavity. During my research I found soundcoat plaster which is suppose to make the wall airtight. Now can i apply this straight on top of the existing plaster? Their is a few crack in the existing. Nothing major. But with this plaster being described as air tight I'm assuming it will help block out sound. Anyone had any experience with this? The wall is solid brick as well. The house was built late 30s early 40s

 

[Michaelsf90]

So the house is late 30s early 40s. I'm looking at soundproofing the party wall by creating a stud wall an inch away. I believe when it comes to soundproofing the cavity is important. Now it's not rising damp I'm bothered about it's more moisture/condensation. The stud wall is fixed to the floor, ceiling and the side walls. One of the side walls is an external wall but it's literally a few inch that's going to be covered. The question is will any of what I'm going to do cause damp through a serious lack of airflow. The main aim is to make it airtight but I'm thinking is making it airtight not impossible? Air can get through the tiniest of cracks. It's a cavity subfloor underneath which is vented for airflow. I may be overthinking but I don't want to cause damp on my or next doors side

 

[essex123456]

You have to have the gap otherwise your new stud wall will just act like a speaker cone. You want to seal any gaps with an acoustic sealant or intumescent sealant. You are trying to separate the new wall from it's surrounding to stop vibrations being transmitted, you then put rockwall in the gap to damp other frequencies Your cavity sub floor will transmit any airborne sounds. If your floor joists go through to next door there is not a lot you can do to separate that part.

I built a stud wall in this way and then used two layers of soundbloc, staggered so joints were overlapped. It's a 1930's semi. But I have solid floors.

I think you are over thinking the damp.

 

[Michaelsf90]

I think so as well. The joists luckily don't go through to next door but the first joist is about 10mm from the wall so I can't really stick any rockwool in. I was thinking of putting down some sbm rubber matting down on the floor and on the ceiling which will be inside the small cavity to cover flanking noise. Then in the next two joist spacings I will put 50mm rockwool. What rockwool did you use and do you feel it has made a difference?

 

[essex123456]

Hi I can't ember the brand of rockwool, it has made a difference but to be honest our neighbor is not to noises, but we could here her TV. It's cut that out. I do wonder if three layers of soundbloc would be better?

 

[Michaelsf90]

To be more specific. People can get confused with damp and think it's rising damp not the condensation type. I'm trying to cover all angles. I made a start yesterday and have already come across a problem. The joys of DIY

 

[Michaelsf90]

I was thinking rwa45 50mm and using resilient bar. I have done as much research as possible. I imagine three would be better but imagine the weight. I'm using soundboard on the ceiling as well. I'm dreading lifting those