You can't tell from a house's age alone. The proper answer comes from an Electrical Installation Condition Report (EICR), which tests the wiring and says whether it can stay, needs repairs or needs replacing. Warning signs that make an EICR worth booking soon include scorch marks, a burning smell, warm or buzzing sockets, rubber or fabric-covered cable, round-pin sockets and an old fuse box with rewireable fuses.
Is old wiring dangerous right now?
Usually not immediately, but some signs need action today. If you see or smell any of these, switch off the affected circuit or the main switch if it's safe to do so, and get it checked:
- Smoke or flames
- Get everyone out and call 999.
- Burning smell or scorch marks
- Brown or black marks around sockets, switches or the board.
- A socket or plug that feels hot
- Warm to the touch, or plastic that looks melted.
- Buzzing or crackling
- From a socket, switch or the fuse board.
- Shocks or tingles
- From a switch, appliance or metal fitting.
Does an old house automatically need rewiring?
No. Age alone isn't proof. A house wired in the 1970s or 1980s with PVC cable may still test well today, while a much newer extension done badly may not.
What matters is the type of cable, its condition, how it was installed and how it tests. Plenty of 1930s semis and Victorian terraces in and around Leicester have been rewired at some point, and some only partly. The only way to know what's behind your walls is to have it inspected and tested.
What are the warning signs that wiring is past its best?
Some signs point to wiring that is very likely due for replacement. Others suggest the installation needs updating or repairing. Any of them is a good reason to book an EICR.
- Rubber or fabric-covered cable
- Common before the 1960s. The insulation goes brittle and crumbles.
- Lead-sheathed cable
- Grey metal-covered cable from early in the 20th century.
- Round-pin sockets
- A strong sign the wiring behind them is very old.
- No earth on lighting circuits
- No green-and-yellow or bare earth wire at light switches and fittings.
- An old fuse box
- Rewireable fuses, a wooden back board, or no RCD protection.
- Frequent trips or blown fuses
- Especially when no single appliance is to blame.
- Scorching, warm sockets or buzzing
- Signs of loose connections or overloaded circuits.
- Not enough sockets
- Extension leads and adaptors in every room.
Do red and black wires mean my wiring is unsafe?
No, not by themselves. Red and black were the standard UK colours until 2006, when they changed to brown and blue. Red-and-black PVC cable can still be in good condition.
Old colours tell you the wiring is at least that old. They don't tell you whether it is safe. A test does. If someone says you need a full rewire only because the wires are red and black, ask to see the test results that back it up.
What do the codes on an EICR mean?
An EICR lists anything that falls short of the current Wiring Regulations (BS 7671) and gives each item a code. Any C1, C2 or FI makes the overall report unsatisfactory. C3s alone don't.
- C1: danger present
- Risk of injury now. Made safe straight away, often before the inspector leaves.
- C2: potentially dangerous
- Not dangerous this minute, but could become so. Needs fixing urgently.
- C3: improvement recommended
- Doesn't meet current standards but isn't unsafe. Worth doing when convenient.
- FI: further investigation
- Something needs looking into further, without delay, before it can be coded.
What can I check myself before calling an electrician?
You can look, but don't open anything up. Check the fuse board for rewireable fuses or a missing RCD test button. Look at the sockets: round-pin, cracked or loose ones are worth noting. If cable is visible in the loft or under the stairs, note whether it's grey or white PVC, or black rubber or fabric.
Take photos and write down any trips, smells or warm sockets. Taking off socket fronts or light fittings is where DIY should stop. It isn't worth the shock risk, and an electrician will check those points properly during testing.
What happens if the EICR says I need work?
It depends on what the report finds. A few C2s, such as a damaged socket or missing bonding, are usually fixed as individual repairs. The house doesn't need rewiring because of them.
When problems run through the whole installation, such as crumbling rubber cable or most circuits failing insulation tests, a rewire is usually the sensible answer. That can be partial or full:
- Partial rewire
- One floor, an extension or a set of circuits replaced. The rest tested and kept.
- Full rewire
- Every circuit, socket and switch replaced, usually with a new consumer unit.
How can I keep my wiring in good shape?
Get it tested regularly and fix small things before they grow. Guidance commonly suggests an EICR for owner-occupied homes every 10 years and at each change of occupier. Rented homes in England need one at least every 5 years.
Press the RCD test button every few months. Don't overload sockets with adaptors. If you're planning a kitchen, extension or redecoration, test the wiring first, because rewiring is far easier before the walls are finished.
If a rewire is needed, we price it after a survey and give you one fixed price before any work starts.
Questions
Can I get a mortgage or sell a house that needs rewiring?
Usually, yes. Surveyors often flag old wiring and recommend an EICR, and a buyer may use that to renegotiate. Having a recent report helps either side understand the real condition rather than guess.
How long does an EICR take?
For a typical house, usually a few hours, depending on its size and the number of circuits. The power needs to be off for parts of the test, so plan around it. You then get a written report with the results and any codes.
Does a C3 mean I have to do the work?
No. A C3 is a recommendation, not a requirement. It means something doesn't meet the current standard but isn't considered unsafe. Many people deal with C3s when they're doing other work, such as a new kitchen.
Is it worth rewiring before I renovate?
Yes, if the wiring is old. Rewiring means chasing walls and lifting floors, so doing it before plastering and decorating saves doing the work twice. It's also the cheapest time to add extra sockets, lights and outdoor points.
Do landlords have to rewire old properties?
Not automatically. Landlords in England must have an EICR at least every 5 years and fix any C1, C2 or FI items within 28 days, or sooner if the report says. If the report shows the wiring is beyond repair, a rewire may be the only way to comply.