Uneven external sandstone wall - how to dryline

[zacha4]

My Living room is long and thin and the two ends of the room are on external solid sandstone walls. We have removed the very old fibre board which was battened off the lime plastered walls

I would like to dryline the wall to add some insulation to it but was not sure how to do it and what to do it with

My initial idea was to put up some studwork supported from the floor and ceiling and not the wall to give a few inches of air for the wall to breath as the wall is not flat enough to apply battons direct to it and then add some insulation 50mm either on the back of the battons or in the studwork gaps and then face the battons on the roomside with duplex plasterboard.

Or should I mount the insulation as close to the wall as possible and then leave an air gap to the plasterboard.

The other question would be what insulation as I assume it needs to allow water vapour through so the wall can breath or does it if the insulation is against the plasterboard and there is some space between the wall and insulation - someone also mentioned should I also put a vent in through the plasterboard into the room

Lots of questions I know but it seems so many ways of doing it or would the simply thing be just buy some thermal plaster board and just attached it direct to the battens, I had thought of this but the price per board makes it a more expensive option.

 

[phil8340]

Hi

There are 2 ways I would tackle this:

1)The best way would be to re-plaster with lime mortar, this is not hard to do. Also it can be fair cheap if you do it yourself. Solid stone walls are not cold if working correctly. e.g Lime plaster internal, Lime pointing or render external.

2)A small 2x2 or 3x2 stud wall with a breather membrain stapled to the back, the insultion in the middle and plasterboard internal. With this the stud must not touch the wall, and use stainless steel screws to fix to wall. I would put some small air vents in the studs wall to.

Hope this helps

 

[tommyl18]

Are the walls damp?

 

[zacha4]

I dont think it is damp but the wall does need to breathe according to my father as behind one wall there is a earth bank higher than the bottom of the wall