Works finally started on the 2nd August and the walls are up! The delay has simply been because our main contractor has been on holiday and the ground took quite a while to prepare.
Anyhow, at last progress has been made and we are still optimistic that we will be watertight by the end of September. That is assuming the window suppliers come back from holiday and actually answer emails.
Foundations dug, gravel base down
Isoquick base constructed