Interesting the "hidden" junctions between different types of cables.
I struck once a house which was sold as been rewired. yeh yeh, the cables from the fuse panel were all new TPS up to under the roof. then a row of stripconnectors and terminated in the old VIR and TRS cables.
I was called out to investigate intermittend flickering lights.
Whoever had done this job should loose its electrical registration if it was an electrician or a cowboy.
Of course I quoted for a full rewire and the job was brought up to a safe standard
It's interesting that in the USA Aluminium is used a lot in house wiring, considering the relative high currents drawn by appliances at 110 Volts.
I have this not seen in New Zealand, and all cable here is made in copper for house wiring.
Streetcables are copper or aluminium here as are distribution transformer windings.