I have an extension going on to my house and it has engineered joists. I am going to run cables in steel tray, for tidiness, and I am assuming this would be considered an ECP and should be bonded (that makes obvious sense to me). It will carry ring and lighting circuits. I cannot imagine that more than 10mm2 would be required for this, but every time I read new guidance they seem to have upped the ante. What do people think? And do you use link jumpers between sections of tray, or are the bolts sufficient? I've not seen anything to suggest that copper jumpers are needed, and we don't use them in datacenters (the day job), but that's just CAT7 and fibre.
Also because Reasons there are no spare ways on the earth block on the board. Do I have to source an earth block of more than 8 ways or is it legit to join two blocks together with 16mm2? I don't want to look like a pillock and have the sparks refuse to energise the circuits when done.
Thanks
