01/09/2026
⚡ VERDIGRIS – A WARNING SIGN YOU SHOULDN’T IGNORE ⚡
Ever noticed a green, gooey liquid around old electrical cables that looks a bit like Fairy Liquid? 👀
This is commonly known as verdigris and can be found in older electrical installations, particularly wiring dating back to the 1960s and 1970s.
Older PVC cable insulation can deteriorate over time, with components of the plasticiser migrating out of the insulation. When this reacts with the copper conductors, it can produce the distinctive green, sticky residue.
⚠️ This is a sign of cable deterioration and should be properly assessed by a qualified electrician.
We recently came across this in a property that hadn’t been rewired since the 1960s. Given the age and condition of the installation, our recommendation was a full rewire rather than continuing to rely on deteriorating cabling.
🏠 Old wiring in your property?
⚡ Not sure when it was last rewired?
🔍 Seeing green residue around cables, switches or sockets?
Get it checked.
NHM Electrical
Keeping your electrics safe, reliable and up to standard. ⚡