Direct bond or not...?

[mc497]

I have just had an extension built and it is now being boarded out.
The builder has battened all of the new blockwork and screwed plasterboards to it (fine).
But two of the walls inside the new extension were previously outside walls with a tyrolean finish that has been painted.
The builder has said he will board these walls direct bond method.
Is this the right thing to do, will the boards be prone to damp...?
Any advice ...!

 

[Micilin]

If there is a damp course , it is not too high, and the wall is not damp you should be okay as long as there is nowhere damp can seep in where the old and new butt together.

The substrate should be sound before you stick to it, unless you aslo use nailable plugs or IDP fixings.

Hard to tell without seeing it.

Why did he batten the new blocks if not doing this wall? He may probablyhave good reason, but again hard to say . Don't be afraid to ask, he may well put your mind at rest.

If you are worried about the wall, get him to fix a damp proof membrane to the wall , returned 400mm onto adjacen wall and then batten and board it.