Andrew Gabriel wrote:
In article ,
Hugo Nebula abuse@localhost writes:
The only Building Regulations requirement for a non-loadbearing wall
is airborne sound insulation. One layer of 12mm p/bd each side and
25mm mineral fibre between the studs will suffice. The studs may be
75mm timber or 45mm metal. There's no requirements for robustness or
impact resistance.

I'm amazed 25mm mineral fibre would make any difference.
Is this just the loft insulation type stuff, or something
much denser?

Probably denser. The two sheets of plasterboard will do most of the
sound deadening: you normally then back that up with somethng to dampen
panel resonance that makes things sound 'boomy'