Drylining external wall recommendations

Tuco88

Hello,

I am installing K16 Kingspan insulated plasterboard onto an external wall. It's the cavity block (Hollow Block) used to construct the house, so no cavity insulation and not a real cavity too. The wall was damp behind the previous plasterboard and battens (Never used DPC behind battens some rotten)

Question is, is there any issue with fixing the insulated plasterboard direct to the wall with mechanical fixings, space is a factor. Or must it be battened out with DPC and screwed?

Is there any sealer worth applying to the wall prior (Recommendations welcome)

I am going to apply an external sealer to the outside.

Thanks

mickdw

Hollowblock wall is a very poor construction.

You certainly should not fix direct to wall. Considering you see the wall damp, it would be madness to fix direct to wall.

Tuco88

Don't tell me about it, id rather the place was made out of chocolate.

I would have thought the phenolic insulation was so what moisture resistant It could go directly on. Better go with battens so I can just size down the board thickness to make up the difference.

The house will be externally wrapped in insulation at some stage.

whizbang

If the house is to be externally wrapped, the hollowblock cavity must be filled. Otherwise you might as well fix the insulation to the garden fence.

External insulation will sort the damp problem, but :

Address the damp first in case theres some other cause. Its possible its just condensation but if battens were rotten, then theres a big problem.