Building an internal 100mm stud wall on a first floor (metal-web joists) deck to separate two bedrooms in a timber frame build.
There will be no doors or sockets in the wall.
Floor joists at 400 centres run perpendicular to the partition wall, ie. from under one room to under the other room.
I will double plasterboard one or both sides of the partition, artight seal perimeters, install 75mm sound type mineral wool.
(There are two other internal stud walls on this level but they both have doors in them so not worth as much effort in preventing sound travel.)
For the purposes of reducing sound transmission between rooms - should I build the partition directly onto the floor joists and split the floor boarding (OSB T&G) between the two rooms or let the floor ply run continuous under the partition?