In my kitchen off shoot I have a solid 9" external brick wall. The kitchen has been totally stripped back exposing the brickwork and the roof void above the area.
I have looked at the options for insulating it on DIY Doctor and for various reasons I have opted to create cavity wall by installing a stud wall 50mm from the exposed brick.
I have installed a couple of airbricks above floor level in the brick wall to ventilate the cavity and will use rockwooI (left over from a previous job) to insulate between the stud timbers. I will then use visqueen as a vapour barrier (again I have some left over) between the insulation and plaster board.
I have a number of queries that I hope can be clarified by your good selves as:
1. Do I need to install a breathable membrane between the exposed brick surface and rear of the timer stud wall. If so can I use Croma Vent 3 (again left over from another job) that is used on roofs between the batton's and tiles. If yes is it installed the same way as on a roof i.e. printed side facing outward.
2. Would the breathable membrane be attached to the brick wall or the rear of the stud frame.
3. When insulating the roof void above the stud wall, would the insulation go right up to the brickwork or would it be left 50mm short to maintain an airflow between the cavity and the roof void which has roof vents installed.
Hopefully I've explained clearly what I'm hoping to achieve.