We've got the builders in adding a two storey extension to our Bradstone house.
Question. They've done the footings and their doing the blockwork for the inner skin. However, they aren't tying it into the existing walls. They're putting in plenty of wall ties to join the inner to the outer skin, and the chief brickie assures me that he's going to tie in the outer skin by interleaving alternate courses. Will this suffice to make the walls sufficiently robust? Or should I ask him to tie in the inner skin as well?
TIA
Edward