Insulation down and damp proof

The base is nice and flat

 I checked and it is square (you measure across the diagonal and if A=B then is should be square)

Time to cut and drop in the Celotex floor insulation:

I put DPM on top of the bearers, under the walls. Will also do the same under the floor board joists. Don't expect upward water ingress but you never know.

Base wall logs in place.

The base you can see where the double doorway will go.

To left will be two windows and another will go (yet to decide) on right wall or left wall.