Attaching drywall to fiberboard and lightweight concrete

[Badenbaden]

Hello!
I am going to attach regular 13mm gypsum boards onto tretex.
The thing is that I discovered there are no wooden studs behind the tretex, but rather lightweight concrete.
So the tretex is nailed into the concrete.
My question is how I can most easily attach the gypsum boards without having to tear down all the tretex and install new studs.
Answers are kindly welcomed.

 

[Jarlingar]

A regular drywall screw that also reaches a bit into the lightweight concrete will hold like a rock. Or preferably a screw with "a bit more thread" like a chipboard screw.

 

[Spikrätaren]

Chipboard screws actually have too small a head to work with plasterboards. It shouldn't be too difficult to take down the tretex...

 

[mgranbom]

We used glue and Dewalt Wall Dog screws to attach gypsum to lightweight concrete. Perhaps there are screws long enough to reach through the tretex as well...?

/M