Plasterboard consists of a layer of gypsum plaster around 12 mm thick sandwiched
between two sheets of thick paper.
With it you can make a 'dry partition'. A wooden framework is constructed and
layers of plasterboard nailed on.
The BBC's 'double Camden partition' consists of two such frameworks, onto which
are nailed a total of eight sheets of plasterboard.
The advantage of dry partitions is that they can be constructed while the rest
of the studio complex is still operational.
Concrete and bricks are very much more messy, making it more likely that operation
will have to be closed down totally.
Dry partitions are sometimes called 'lightweight partitions'.
This is because you can divide a room into two using just two sheets of plasterboard
on the wooden framework.
But by the time you have added enough extra layers for good soundproofing,
it is no lighter than a brick wall providing the same degree of insulation.