Fitting Insulated Plasterboard to a Solid Wall

[It's me]

I have been looking into how to do this and have been finding mixed information. Can anyone give a clear answer, please?

We have solid outside walls which are rendered. The rendering is in good condition as it was re-done last year and there is no damp. The internal plaster is sound.

We wish to put insulated plasterboard on the outside wall where the staircase is, so space is a premium. My initial thoughts were to use adhesive to dot and dab the boards directly to the wall. However, some articles say that this method can result in damp patches and mould on solid walls because the glue creates a cold spot. Instead, they say to use battens.

So which is the correct method for a solid wall? Dot and dab directly to the wall or put in thin battens (1"?) and glue to the battens?

I should be grateful for advice.

Regards,

James.

 

[JP_]

I would recommend using Everbuild Pink Drywall Foam with Kingspan (or other branded) insulation boards, and plasterboard on top of that. The foam is messy to use but sticks well and you won't get gold spots, and the boards have vapour barrier both sides, so you won't need to worry about moisture getting past the insulation and condensing and causing damp/mould on the underside of the insulation.

Cons - might take a little more room, more time
Pros - should have better insulation, better valour control

 

[^woody^]

However, some articles say that this method can result in damp patches and mould on solid walls because the glue creates a cold spot.

That's more likely with plain plasterboard, not insulated board.

You'll need to knock all the existing plaster off.

Battens with a PIR foam between and across is more efficient, than any insulated plasterboard, but not always practical or possible

 

[It's me]

Thank you both for your replies.

You'll need to knock all the existing plaster off.

Why do I need to do this? The plaster is sound. We have a very thin skim of plaster on our walls, covering a thick layer of very dense concrete. Removing this usually ends up taking lumps of brick with it, needing the wall to be plastered again to make it flat enough to work with. This happened when we worked on the kitchen and the bathroom walls.

Regards,

James.

 

[JP_]

Yeah, I didn't bother taking plaster off my walls when I put insulation up. Only rooms I removed plaster was old kitchen and bathroom, as I knew these had been damp and mouldy so wanted a fresh start. Also, the foam adhesives stick much better to plastered walls than brick if you use that method.

Removing plaster is very very dusty!