⚠️ Old Electrical Wiring: What You Need to Know About Vulcanised Rubber Wiring ⚠️

What Is Vulcanised Rubber Wiring?

Vulcanised rubber-insulated cable (also known as VIR or VRI) was commonly used in homes built or rewired between the 1920s and 1950s. It has a rubber outer sheath and sometimes a fabric braid over the top. It looks old – and it is.

You’ll typically find it in:

• Pre-1960s properties

• Round black or brown cables, sometimes cloth-covered

• Lofts, under floorboards, or in old light fittings

An explanation from Richard Speller (Speller's Sparks Electrical Services) about the dangers of Vulcanised Rubber Wiring...

Why It’s a Problem Today?

Time hasn’t been kind to rubber wiring. Here's what happens as it ages:

✅ It becomes brittle and cracks – exposing the live wires inside

✅ The insulation can fall off completely – increasing fire and shock risk

✅ It can’t handle modern electrical loads – homes today use far more power than when this wiring was installed

✅ It may not be earthed – which is now a legal safety requirement

⚠️ It's not just outdated – it's dangerous. Most insurance companies won't cover damage caused by old wiring, and it won't pass modern safety inspections (EICRs).

How to Spot It?

If your home still has:

• Black or brown rubber cabling

• Bakelite switches or fuse boxes

• A mix of modern and very old wiring

• …it’s worth getting a proper inspection.

Here you can see the rubber wiring, the off-colour brown/red and it's also far larger than the standard copper PVC cable

A picture of the consumer unit - where you can still see the larger vulcanised rubber wiring...

What’s the Solution?

If it can be removed or replaced then a full or partial rewire by a qualified electrician may be necessary - however I was able to recently remove one leg of the cable and so a rewire was not necessary.

This means:

• Replacing old rubber wiring with modern PVC-sheathed cable

• Ensuring sockets and switches are earthed

• Installing an up-to-date consumer unit with proper RCD protection and AFDD protection

Final Thoughts from me…

“If you’ve got vulcanised rubber wiring in your home, don’t wait for something to go wrong. I’ve seen this stuff crumble in my hands. It’s not scaremongering – it really is a ticking time bomb. A rewire might feel like a big job, but done properly, it’ll last you decades and keep your family safe.”

You can book in electrical work with my by going to my website or calling Rich now on 01761 325 007!

Website: www.spellerssparks.co.uk

Call: 01761 325 007