old drywall walls with no studs

[johnbuckley]

This post didn't seem to fit any forum category so aplogies if it's in the wrong section.
My daughter bought wet wall for hwr bathroom and muggins has been tasked to make it work!
I'm not particularly happy with the wet wall as it is the hollow pvc type (pic attached) however, it's what we've got so I need to work with it.
My question relates to the fact that the plaster board walls are of an old type which have no studs and just have an 'egg box type inner between both sides of the wall (pic attatched).
My question is, when I glue the wet wall to this plaster board wall How can aything be screwed to the wet wall without crushing it?
Main issue will be a small radiator.
My first thoughts is to drill the wet wall and plaster board, insert a drywall anchor all the way through to the dry wall and then insert a spacer the thickness of the wet wall to prevent crushing.
Any thought or words of wisdom would be appreciated please.
Mods, feel free to move this post into a more relevent section if need be.

 

[oldbutnotdead]

Is the radiator hanging off the eggbox wall now? If yes then don't worry about crushing the placcie- it is fairly robust. If you are really paranoid just cut some 10mm long disks off a broom handle, drill broomhandle-sized holes in the placcie where the screws for the rad go, drill 6mm dia holes in the broomhandle discs, silicon round them, fix through them.
Think your problem is more likely to be fixing to the eggbox nonsense...easiest way out might be a floor standing cast iron (or replica) rad....

 

[johnbuckley]

Is the radiator hanging off the eggbox wall now? If yes then don't worry about crushing the placcie- it is fairly robust. If you are really paranoid just cut some 10mm long disks off a broom handle, drill broomhandle-sized holes in the placcie where the screws for the rad go, drill 6mm dia holes in the broomhandle discs, silicon round them, fix through them.
Think your problem is more likely to be fixing to the eggbox nonsense...easiest way out might be a floor standing cast iron (or replica) rad....

Thanks for your reply.
Yes the rad is attached to the nightmare wall via cavity wall plugs, I was just wondering about options when fixing stuff to walls when this type of wet wall has been fitted; your broom handle idea is handy, thanks.
I have never come across this type of wall before, must have been cheaper back in the day!