In article ,
Mary Fisher wrote:
I've just bought a house which was built in 1965. It has a modern
consumer unit but having just removed a light switch I notice the wires
leading to it are black and red.

At what point does a rewire become necessary?

When it's a) illegal (which yours might be) or b) before it's dangerous.

Please explain how you think wiring in a house built in '65 could be
'illegal'?

Don't risk it, install modern wiring, regulation compliant.

Perhaps some proper inspection and testing might be a cheaper alternative
to blindly replacing things?

The likely major thing that doesn't meet current regs is that lighting
circuits may not have an earth. But this is by no means certain with mid
'60s wiring.

--
*Heart attacks... God's revenge for eating his animal friends

Dave Plowman London SW
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