Internal panelling on lime plastered wall

Good Evening & Merry Christmas to all.

If anybody is on the forum this evening and fancies giving their opinion on the current topic being discussed by our extended household on Christmas evening :lol:

What is the best way to have full height wooden panelling internally on a lime rendered wall (external), but most importantly that allows breathability?

Current walls are dry and on 2nd floor of property.

Current suggestion.
-3x2 stud, not touching wall
-Sheep’s wool insulation (Celotex & Rockwool cavity wall insulation being suggested too)
-Moisture recent MDF for panelling
-Air Brick on outside
-Vents on panelling

Thoughts ??

Panelling spaced off the wall behind on battens - and vented top and bottom to allow air circulation - would be my first thought. Roofing battens are cheap and pressure treated.

A few gaps in the battens to allow air between the vertical "cells" would be a good idea as well.

If there is a ventilated gap between the wall and insulation, Celotex type boards will provide much more effective insulation than sheep's wool and you won't need to worry so much about breathability. Sheep's wool is prone to insect attack (wool moth for example), which fibreglass & rockwool is immune to (and is still breathable). Using a fibre insulation, you'd need to stretch some mesh tautly across the back of the battens or studs to prevent it from making contact with the wall.

When I insulated a solid brick wall last year, I screwed 2x1 roofing battens to the wall, and then fixed Celotex type boards over the top, taping the joints with aluminium foil - Have a look at the "warm batten method". It has certainly made the room much easier to heat, and it is nice & warm in there now.

Is your concern simply to resolve any dampness on the interior, or are you also insulating as well? I assume the lime rendered wall is some breathable stone? How thick is the wall? Also I assume that the wall itself does not have any type of RWG fault or high ground causing dampness? These are surely far more important than the internal breathability of the wall.

If OK to the above, I would add studs and then your panelling with gaps top and bottom to keep the gap vented. Celotex surely is not breathable, nor have I ever regarded rockwool as breathable. Even sheepswool batts (I've never had issues with my Thermafleece) seem of little point for the cost.

My 1850s house has 16 inch limestone walls and I sorted the dampness (roof, RWG, drains, high ground) in 2010/11, and then overhauled the sash windows by 2017. I have NEVER had any issue with dampness (since early 2011) or cold (since doing the sashes) even after doing some internal tiling.

Matthew

@Matthew - No damp issues in the room. The wall is 2ft thick & lime pointing is good on the outside.
I think the main questions are based around breathability/correct methods that won't cause issues moving forward. But on the basis that stud/battens will go up to fix the panelling too, insulation should also be considered.