How NOT to do it!

This is what I uncovered when I opened up the partition that shows a strange horizontal line of damp approximately 2' off the floor.

Surprisingly the timber skirting was alright with no excessive moisture content but I was not expecting to find such poor workmanship. Obviously the sole plate had rotted but rather than repair the new screed was laid up to it and into it where it had decayed. The moisture content of this timber is also acceptable and I am none the wiser as to why or where the damp has come from. It is not really showing to the other side which is also strange.

I think that I will have to cut off the base of the studs, remove the defective plate, make good the screed with damp proofing and lay a new plate and let in new sections of stud.

This of course will put the work back a week......!