What to do with wall / what is this stuff in existing wall?

[sidhead]

Hello,

We have a 18th century cottage that's turned out to be a bit of a renovation. We've recently ripped the kitchen out of one of the downstairs rooms ready to make that room into an office.

After taking off the tiling and the cupboards, it's taken some good chunks of the plaster off, which has revealed some plastic slatting. Wondering if anyone knows what this is? I tried searching Google but not getting any joy. It's different to the traditional lath & plaster upstairs in the old bit of the cottage for sure, and I suspect it's some sort of moisture block.

 

The metal electrical backboxes that were sunk into this wall have gone totally corroded. On the one by the window this is because the gutter in the corner was blocked and there was a puddle in the back box, but the others were technically dry, but clearly get at least moist probably in winter or at least related to the fact this was a kitchen and it was behind the cooker etc.

Wondering what to do with the walls. I had intended to plasterboard over it but I think more needs doing to control the damp that must be in that void between the exterior bricks and the inner wall lining. Should I remove the existing interior side (including this slatting) and build a stud infront of it so it can be better insulated or moisture barrier? Also reading that old houses should have certain materials etc to aid breathing..

 

Edited May 6, 2022 by sidhead