y builder is currently building the walls to my extension. The wall spec is 100 brick, 10 cavity, 90 insulation, and 100 block. Building control told me to ensure the cavity is clear from mortar and anything else.
My builder seems unable to do this, however. Every time I go outside and check on the courses he has completed it is full of mortar that has been pushed out from the brick and against the insulation. He's complained that it is a difficult detail (the 10mm cavity) and that there are no tools to help. He can clear the mortar from the last course using the trowel but some (a lot it appears) falls way down where he can't reach and builds up.
How important is this? Do I have to tear down 50% of the walls and start again!?