On Sunday, 17 March 2019 14:24:48 UTC, Mathew Newton wrote:
On Sunday, 17 March 2019 14:12:04 UTC, JimK wrote:

If you are plastering walls around the opening then you can apply
plaster direct to the lintel just press the initial bonding coat into
the gaps to maximise adhesion.
I wouldn't do that as if the rest of the ext walls are insulated
the reveals will become the coldest place = condensation, mould
etc.

Yes, I am keen to ensure there is at least some insulation around the reveals (although the door frame width means there won't be all that much).

I also don't think plasterboard adhesive necessarily sticks well
to the insulation of insulated plasterboards.
Depends what the insulation is faced with ? Paper? Foil? Foam?

I'll be making my own plasterboard+insulation sandwich and so it'll be foil backed. I too had read that dot-and-dab adhesive doesn't stick well to it, but it seems that most 'tube' adhesives do.

PVA loves foil, but isn't gap filling. I'd use something reasonably waterproof, that way come what may you won't have any additional problems. Anything waterproof really.


NT