Insulating a partition wall

HaydenB

Can anyone please suggest a decent, but cheap, way to insulate partition walls? It isnt for thermal reasons but more for acoustics.

phil24_7

Just to be sure, are you talking about an internal wall between 2 rooms, and do you have access to both rooms?

HaydenB

Yes and yes. 3x2" timber, plasterboarded and skimmed (once insulated).

Grenage

Fill it with as much rockwool as you can; the denser the better. You can get fibreglass batts, which would be ideal.

phil24_7

When I did 2 of my bedrooms I used high density rockwool type stuff in between the studs. I cut so that they fit snuggly between the studs and left an equal gap at either side. It wasn't cheap and I got it from Wickes (can probably get it much cheaper from a builders merchants or somewhere like Encon).

I then double boarded, firstly with soundboard which had all the joins and right around the edge sealed with acoustic sealant (available in big tubes along with a special gun, from toolstation), then with a regular layer of plasterboard.

This worked out to be a similar thickness to the original lath and plaster so meant architraves all lined up. It is many times quieter than a regular stud wall and noticeably quieter than a lath and plaster wall. It made it very difficult to hear my baby in the next room so we had/have to keep the bedroom door open!

Regards
Phil