Lime plaster walls insulate

[Bouba]

Please advice as have been given different opinion on how to remedy this. 1930 house which has solid 9" walls.

I have a small section of which has been stripped back to bare brick. Plasterer wants to use hardwall and then plaster it, then use some kind of metal channel and insulated plasterboard on top. Outside this wall is pebbledash.

Is this correct. Does old house not have lime plaster and allowed walls to breathe. Please advice if he is using correct technique as he has asked me to get the materials. Paying him 2 days labour, so do not want to be fobbed off and have problems later down the line.

Thank you.

 

[SparrowHawk99]

Are they basement walls or above ground level?

 

[Bouba]

Above ground level. The flank wall of the house shared with neighbour. The neighbour has build his extension away from this wall so basically, a freestanding wall.

 

[SparrowHawk99]

There are many ways to do the job, I think hardwall is a reasonable suggestion, if he has mentioned doing it that way it's probably safe to say he thinks the wall is dry enough, which is good. I'm not familiar with using metal channels. In my situation the walls were in a basement and cement rendered with a little waterproofer and then thermal plasterboard was fix foamed to the cement render and then plastered. There are so many ways to do it.

What are the walls? Is there a DPC? Are the walls wet? Are there signs of rising damp?