BTW I took some resistance readings for the main ring main in the house and the readings I got was 1.8 Ohms for the CPC and 0.8 Ohms for both Live and Neutral. Are these OK? Hope to finally permanently wire in the garage this weekend and will take readings for the garage ring main.

I do not know if this is common across LAs but in ours the BCO inspect the work but the actual testing is contracted out to electricians.

Richard