Thanks for that .. to do mean 5 sided pocket ? ie - base and 4 sides?
Sould we fill with insulation plus cement - or just cement? - How thick?
Sorry for the ignorance!
Our attempts to replace few cracked tiles by the back door has uncovered a can of worms.
The cavity wall had been filled to surface by insulating material overlain by a layer of mortar - now removed leaving us with a hole ! Should we fill it with insulation?
It has been suggested that we span...