What is cotton wiring and why is it dangerous?

Cotton wiring is an outdated type of electrical cable insulated with braided fabric and rubber. Over time, the insulation becomes brittle and exposes live wires, creating fire and shock hazards. Homes with cotton cabling should be rewired by a licensed electrician.

Old Wiring In Homes

If your house was built before the 1960s and hasn’t been fully rewired, there’s a good chance it still contains cotton insulated electrical cabling.

We still occasionally find it in homes across Yarraville, Braybrook, Footscray and Williamstown and older parts of Melbourne’s west.
It is often tucked away in ceiling cavities, old work sheds or inside switchboards.
And while it might still be carrying power, it’s far from safe.

Here’s how to know if you’ve got cotton wiring, why it’s a risk, and what to do about it.

1. What Is Cotton Cabling?

Cotton wiring refers to old electrical cables insulated with:

• Braided cotton or cloth sheathing
• A layer of vulcanised rubber insulation underneath
• Sometimes, early PVC insulation in later retrofits

At the time, it was the best available option. But age, heat and exposure cause the insulation to brittle, crack and peel away, exposing live wires.

2. How to Tell If You Have It

You might not know until someone inspects it but look for:

• Black, braided fabric around old wires
• No earth wire (many cotton-wired circuits lack grounding)
• Fuse box with ceramic fuses (often installed alongside cotton wiring)
• Homes built pre-1960 that haven’t been fully rewired
• Original lights or switches with no visible cabling upgrades

We’ll confirm what type of wiring is present during a Home Electrical Inspection.

3. Why It’s Dangerous

Even if the wiring “works,” cotton cabling is a serious safety risk because:

The insulation breaks down

The rubber hardens, cracks and flakes away with age, exposing live copper conductors.

There’s usually no earth

Without grounding, there’s no path for fault current to trip safety switches. This increases the chance of shock.

It doesn’t meet modern standards

Cotton wiring doesn’t comply with AS/NZS 3000 electrical rules, which require insulation integrity, RCD protection, and grounding on all circuits.

It creates a fire hazard

Exposed wires inside walls, ceiling cavities or near timber beams pose a clear fire risk—especially under load or when insulation shifts.

4. What You Should Do

Don’t disturb it

If you’ve seen exposed cotton cabling in your ceiling or switchboard, avoid touching it. Moving the wires can cause the brittle insulation to flake off entirely.

Don’t patch around it

Adding new light fittings or sockets onto old cotton circuits can create mixed compliance issues.

Do get a licensed electrician to inspect it

We’ll check the insulation resistance, circuit layout and safety switch coverage—then provide a rewiring plan if needed.
Book an assessment through our Emergency Electrician or Fault Finding pages.

5. How We Handle Rewiring

If your home still uses cotton cabling, we’ll:

• Identify and isolate all affected circuits
• Remove old wiring from ceilings, walls or conduit
• Install new TPS cabling with proper insulation and earth
• Separate lighting and power onto dedicated circuits
• Upgrade switchboards if required for RCD protection
• Issue a Certificate of Electrical Safety upon completion

Rewiring is usually staged room-by-room to minimise disruption.

6. Can You Still Get Insurance?

Many insurers won’t cover fire damage from outdated electrical systems especially those involving cotton cabling.
Even if you’re currently covered, failing to upgrade a known hazard could cause a claim to be rejected later.
We can provide documentation showing that rewiring work was completed by a licensed contractor.

FAQs

Is cotton wiring illegal?

Not exactly, but it doesn’t comply with modern safety standards. If found during renovations or inspections, it should be replaced.

Can I just replace the power points and keep the wiring?

No. New fittings won’t solve the risk of deteriorating insulation behind the walls.

Is rewiring the whole house expensive?

It depends on the size and access. We often do staged rewiring starting with high risk areas first.

Do you issue safety certificates after rewiring?

Yes. Every job comes with a COES and full compliance with Victorian electrical standards.

Final Advice About Old Wiring

Cotton cabling might still be powering your home, but it shouldn’t be.
We’ll help you replace it with safe, modern wiring that protects your family and meets today’s standards.

Wiring Electricians