There is a crack on the rear wall of my house, running ground to roof. When I bough the house, the surveyor said the crack was caused by subsidence in the distant past, probably in the early years after it was built, and I was told to monitor it.It hasn't changed moved at all in 4 years, so i tend to concur that it is very old subsidence that has long since stopped.
It is a north facing wall, and makes the rear of the house a little colder than it might be, a bit draughty. I now want to fill the crack to prevent moisture ingress etc.
What is the best way to fill this crack ?