Do I Need to Rewire My Old House? Signs, Costs & What's Involved

If you own an older home in Sydney — particularly one built before 1980 — you might be wondering whether the wiring needs replacing. It's a big question, because a full rewire is one of the most disruptive and expensive electrical jobs a homeowner can face. But it's also one of the most important safety upgrades you can make.

How Long Does House Wiring Last?

The lifespan of electrical wiring depends on the materials used and the conditions it's been exposed to:

• Rubber-sheathed cable (pre-1960s): 30–40 years. If your home has this, it's well past its expected life. The rubber insulation becomes brittle, cracks, and can crumble when touched
• Early PVC cable (1960s–70s): 40–50 years. Better than rubber, but early PVC formulations degrade, especially in hot roof spaces. Many are now at end of life
• Modern TPS cable (1980s onwards): 50+ years under normal conditions. If your wiring dates from this era and hasn't been damaged, it's likely still in good condition

Warning Signs Your Wiring Needs Attention

Definite Red Flags (Act Now)

• Burning smell from outlets or switchboard — indicates overheating connections, potentially from deteriorated insulation or loose terminals
• Discoloured or warm power points — a sign of excessive resistance from poor connections or undersized wiring
• Sparking when plugging in appliances — some minor sparking is normal, but persistent or visible arcing indicates a problem
• Frequently tripping breakers or safety switches — especially if isolation testing doesn't identify a faulty appliance
• Visible wiring damage — cracked, crumbling, or rodent-damaged cable insulation anywhere in the home

Warning Signs (Investigate Soon)

• Flickering lights — can indicate loose connections in ageing wiring, especially if multiple lights on the same circuit are affected
• Two-pin power points — if your home still has two-pin (ungrounded) outlets, the wiring almost certainly predates modern safety standards
• Ceramic fuses in the switchboard — homes with ceramic fuse boards almost always have old wiring that needs assessment
• Aluminium wiring — used in some 1970s Australian homes. Aluminium oxidises and expands more than copper, causing loose connections and overheating at terminals

Full Rewire vs Partial Rewire

Not every old home needs a complete rewire. A qualified electrician can test your existing wiring to determine its condition:

Full Rewire

All cables are replaced from the switchboard to every power point, light, and fixed appliance. Required when:

• The wiring is rubber-insulated or early degraded PVC
• Insulation resistance testing shows widespread deterioration
• You're doing a major renovation that opens up walls and ceilings anyway
• The home has a history of electrical faults across multiple circuits

Partial Rewire

Only the most degraded circuits are replaced. Appropriate when:

• Testing shows some circuits are sound while others have failed
• You're renovating specific rooms (kitchen, bathroom) and want to replace wiring in those areas
• Budget constraints mean prioritising the highest-risk circuits first

What Does a Rewire Involve?

1. Assessment and testing — circuit-by-circuit insulation resistance testing to determine the condition of every cable
2. Planning — new circuit layout, power point and light positions, switchboard design
3. Cable installation — running new TPS cable through roof space, under floors, and down walls. In brick and masonry homes, this involves chasing channels in walls
4. Switchboard replacement — always included in a full rewire. New board with modern circuit breakers and RCDs
5. Fit-off — new power points, switches, and light fittings throughout
6. Testing and certification — comprehensive testing and CCEW lodgement

Disruption level: A full rewire is invasive. Expect small holes in walls and ceilings for cable access (we repair these, but you'll need to repaint). If you're planning a renovation, timing the rewire to coincide minimises disruption.

Rewiring Costs in Sydney (2026)

• 2-bedroom unit: $8,000–$12,000
• 3-bedroom house: $12,000–$20,000
• 4+ bedroom house: $18,000–$30,000+

These ranges include a new switchboard, all new cabling, fittings, testing, and certification. They don't include painting or plaster repairs (though we make access holes as small as possible).

Concerned about the wiring in your home? Call Randwick Electrical on 0413 707 758 for a wiring assessment. We'll test your circuits and give you an honest opinion on whether rewiring is needed — or whether you can safely leave things as they are.