Tripping RCDs in older properties
Why it happens here
Decades-old cable insulation breaks down, especially in wall runs that have been extended or disturbed. Moisture in external circuits makes it worse. The RCD does its job by tripping, but the underlying fault remains.
Our approach
We test the full circuit with an insulation resistance tester rather than just resetting the device. The affected section is replaced properly, and we verify the repair under load before leaving.