Fitting a false ceiling

[mikemanc]

I live in a flat with concrete (strucutural) ceilings and have had the flat rewired. The wiring for ceiling lights was buried in the concrete so I've had to have trunking run from the wall to the fitting. I want to hide this by fitting false ceilings.

I'm happy with the method of running battens along the wall and attaching joists to these but how can I attach the joists to the ceiling?

As I said, the ceilings are concrete and have a thin layer of plaster on them.

Thanks

 

[IJWS15]

What is the span?

 

[mikemanc]

What is the span?

Yeah, I can see how that would be useful!

There's 4 rooms:
3.94m x 3.91m
3.33m x 2.82m
2.18m x 1.78m
3.00m x 2.46m

Thanks

 

[ajrobb]

Maybe this might be useful:
http://www.british-gypsum.com/systems/system_selector/casoline_mf.aspx