Cracks after wood burner fitted

[siddaway]

Hi, the woodburner installer cut out a section of plasterboard and replaced it (im guessing with heat resistant plasterboard) behind the woodburner, the problem I have is even after filling, sanding and painting the join between the new section of plasterboard and old the heat makes the board move slightly and I have a constant fine crack at the join location (pic attached)

can anyone suggest the best way to resolve this?

Thanks

 

[Bonni]

In short, physically impossible.

 

[Mr Chibs]

Is the opening larger than a sheet of board?
Otherwise could it not have been installed as one piece? Then you would need to fix it.

 

[Harry Bloomfield]

can anyone suggest the best way to resolve this?

A stainless steel panel, a little larger than the PB panel and spaced 10 or so mm off it - it will hide the cracks and possibly prevent them, but will bounce the heat forward.

 

[johnny2007]

Did they use mesh at the joints when they decorated?

 

[lostinthelight]

The PB and Cement board will have different rates if expansion so virtually impossible to stop it cracking that close to the stove.
How are both boards fixed to the wall,
there shouldn't be any wood touching the back of the panel if it's closer than manufacturers distance to combustibles specs.
You may end up by having to just hide the crack with a narrow trim strip over it, fixed to the wall or panel, which leaves the panel free to expand and contract