How to fix crack in ceiling plaster

Hi,

I've got a crack in the ceiling plaster on the first floor. The paint has detached from the ceiling wood and there is a small gap between the paint and the wood.
I'm thinking of using a tape to fix get that gap fixed - which is basically taping that paint back in place. Then using some polyfilla to smoothen it out and paint over.
Question: Any recommendations on tape which I can use to close that gap?

TIA

 

B Souza, good evening.

Sorry I am confused.

Is the material from which the paint has de-bonded plasterboard or some form of timber, say plywood?

There is a really big difference, including a severe fire risk.

Ken.

 

Hi @KenGMac , thanks for replying. It's plywood, from what I can see. What are your thoughts on what needs to be done.
Attached an image.

Thanks.

 

B Souza, good evening, again.

There are two main possibilities ?

1/. Remove the ply, do it carefully and you will have a template? then fit some plasterboard. and think about adding some insulation into the "void"

Or?

2/. Overboard the Ply with Plasterboard, less messy?

Ken.