I need to run a 10mm earth bonding cable right through the house to
connect the incoming rising main (by the back door) to the main earthing
point next to the CU (by the front door - great!).

Do I need to do this using one unbroken length of cable, or am I allowed
to make a crimped joint to connect two shorter lengths? Reason is that
of course I have a long piece on my reel, but it's just too short to
reach right through the house and I'd rather use it unless the regs say
I can't.

Thanks
David