My place has a room over a carport with a 3.5m horiz. crack (outside & a bit lower inside), about 6 courses up in the rendered blockwork cavity wall that's sits on the lintel over the entrance to the carport.
Is there a best time to repoint (I thought Spring or autumn, somewhere between the extremes of expansion/contraction in winter/summer).
Is there a procedure, obviously I don't just cut out a 3.5m length of mortar course in one hit, and then think about getting some mortar put back in?
What happens when a wall tie is encountered?
What mix mortar goes back in?
What about the various mortar raking tools available from Scre**ix. Are they up to it?
And any tips, generally, would be welcome.