In message
,
sm_jamieson writes
OK, I put loft-style glass fibre insulation compressed to half its
natural thickness in my new stud partitions (they are near doorways
anyway, acoustic wool not required for building regs, but stops the
hollow sound.
However, I want to put in some proper acoustic stuff inside the boxing
around the PVC soil pipe to minimise the flushing sounds. It seems the
decent stuff is at least 45kg/m^3 and best stuff up to 60kg/m^3.
Probably will be delivered due to the weight.
Where is the best place to get this stuff (I am in the Midlands) ?

Is expanding foam not suitable?

regards

--
Tim Lamb