When my 17th cent. timberframed house was renovated 40 years ago a lot
of walls were smoothed up using plasterboard.

I have just discovered that in the area below a window where I planned
to replace the 40 year old radiator with a new one there seems to be
only one leaf of blockwork, and a 5 inch gap and then plasterboard. I
cannot find any studs supporting the plasterboard except at its edges
- the distance from floor to window cill is only 2 feet anyway.

Now obviously a previous, slightly smaller radiator has been hanging
from this plasterboard quite happily for 40 years without falling off,
and the radiator I plan to fit is only a fairly light 400 x 1200
single, nevertheless, I would feel happier with some advise about what
sort of fixing to use.

If I hang it directly from the plasterboard again, what sort of
fixings should I use? Or would it be possible/practical to get a 7 or
8 inch masonry fitting, drill right through into the blockwork, insert
some sort of mega Rawlplug type fitting and screw it all together.

Thoughts please. TIA

Keith