In a pickle with Aquapanel substrate, around a fireplace

[slonik]

Hi,

I'll admit upfront this is a bodge, but I want to try it before having to spend "real money".

I have fitted aquapanel (cement board) on the front of my new hole-in-the-wall gas fireplace, this is where the problems start! (I probably should have used Supalux in hind sight)
The temperature can get to 75C, and I initally plastered it, this has all cracked and come away and Knauf technical support say that this is because it is gypsum based so wont stick to the aquapanel.
They suggest some £100 skim stuff but even then say it might crack above 50C.

So my crazy idea is to "skim" it with tile adhesive and sand down smooth and paint it.

My question is which adhesive would be my best shot?

Thanks
Dan

 

[Tabby Cranks]

You won't be able to sand tile adhesive smooth.

 

[slonik]

You won't be able to sand tile adhesive smooth.

Hi,
Thanks, Is this because it will be too hard?
I think it should still be soft enough the next morning?

Or some other reason?

 

[kilty55]

there is a specific plaster you can use from knauf to plaster over these boards,not sure if its suitable for high temps though

maybe google it and check the spec sheets.