Hi, recently did an eicr on flats, the electrician that wired them is no longer available!?! I made a note of the lack of bonding to the mains water incomer, the builder disagrees and stated that he has had 2 electricians and a lecturer look at this and it doesn't need any due to the amount of copper present, the copper pipes drop about 12 inches below the Worktop before changing to plastic, the tank is also copper. I can't find anywhere that states the amount of actual copper piping required before bonding is necessary.
