Wood wool board on battons with sheepswool

[trimattrdg]

I'm planning on tackling my hallway which is back to brick. My plan is to button out to 50mm depth and add 50mm sheepswool insulation (except windows and door opening) then place 25mm wood wool on top and lime plaster.

After issues with dot and dab before and condensation related problems I'm keen to take a different approach. Does the above seem a fairly safe bet for moisture management and provide reasonable insulation . Any detailing I should be aware of?

The dot and dab before was about 7cm in depth in places so not too concerned about loss of space. The wall is a cavity wall.

 

[a twig]

Lists of useful information in this thread covering both wood wool and wood fibre insulation options and installation methods - in your case I’d just apply wood fibre direct to the walls and plaster over it

 

[aockenden]

Yeah an alternative would be to just upgrade to a thicker wood wool board (if you’re after the insulation improvements), and then “butter” the backside of the boards with a lime mortar and “mush” it directly against the brick (plus mechanical fixings). Then lime plaster on the front as usual.

If you’re dead-set on the battens + sheepswool approach, I’d be making sure to really tightly pack the gaps with the wool so that it makes strong dense direct contact with both the brick and the backside of the wood wool board. This is to make sure that liquid condensation that may occur back there can be reliably “passed off” between all the layers via capillary action, until it migrates all the way to the surface and evaporates off the breathable paint and into the air of the room.