The era of the wiring tells you what to expect. Rubber-insulated cable from before the 1960s is past its life and brittle. Lighting circuits with no earth are normal up to the 1960s. Aluminium cable appeared briefly in the 1970s. Whatever the age, the main earthing and bonding is the check that matters most and is most often missing.
- Rubber and lead-sheathed cable is end of life whatever it looks like. Replace it.
- No earth at the light switch is normal pre-1966 and rules out most metal fittings.
- Age alone does not condemn an installation; condition and earthing do.
- Partial rewires over the decades are why one house can contain four eras at once.
What each era typically left behind
| Era | What you usually find | The concern |
|---|---|---|
| Pre-1940s | Rubber or lead-sheathed cable, round-pin sockets | Insulation is brittle; full rewire |
| 1940s–50s | Rubber cable, rewirable fuses, few sockets | End of life; no RCD protection |
| 1960s | Early PVC, no earth on lighting, rewirable fuses | Lighting earth; fuse board |
| 1970s | PVC, some aluminium cable, more sockets | Aluminium connections work loose |
| 1980s | PVC twin and earth, MCBs appearing | Often serviceable; no RCD |
| 1990s | PVC, MCB boards, RCD on sockets | Usually fine; check the board |
| Any era | Missing main bonding to gas and water | A safety fundamental, often absent |
The last row is the important one. We find missing or undersized main bonding in houses of every decade, including recent ones, and it matters more than most of the things people worry about.
Pre-war: rubber, lead and round pins
An installation from before the Second World War that has never been touched is rare, but partial survivals are common — a lighting circuit in a cellar, a run to an outhouse, a redundant cable still live at one end.
Rubber-insulated cable is the defining problem. Rubber perishes: it hardens, cracks and falls away from the conductor, particularly where it has been warm, bent tightly or exposed to light. A cable that looks sound in the middle of a run may have bare conductors at the ends, inside the switch and ceiling rose where the heat is. You cannot assess it by looking at the visible part.
Lead-sheathed cable appears in grander or earlier installations. The lead itself survives; the rubber inside does not.
Round-pin sockets are a reliable sign nothing has been rewired on that circuit since the 1940s or 50s.
Cloth or braided flex to light fittings, often twisted together and taped at the joint.
There is no partial answer here. Rubber-insulated wiring is past its service life, and the correct response is a full rewire of anything still on it.
1960s and 70s: the two specific issues
No earth on the lighting circuit
Until the mid-1960s, lighting circuits were routinely wired without a circuit protective conductor — no earth at the switch or the ceiling rose. The house functions perfectly, and it only becomes a problem when someone fits a metal light switch or a metal pendant, which then has no path to earth. This is why an electrician will refuse to fit a metal switch plate on an old lighting circuit, and why swapping plastic switches for brushed chrome is not the cosmetic job it appears to be. You can check yourself: take off a switch plate and look for a green and yellow conductor in the back box. If there is none, the circuit has no earth.
Aluminium cable
For a period in the 1970s, when copper prices spiked, some installations used aluminium conductors. Aluminium behaves differently from copper at a terminal: it creeps under pressure and it oxidises, so connections that were tight when made work loose over time, and a loose connection is a heating connection. It is not common, it is not an automatic condemnation, but it does mean terminations need checking and it is a reason to take an inspection seriously rather than assume 1970s PVC is fine.
Rewirable fuse boards
A board with ceramic fuse carriers and fuse wire offers no RCD protection at all. RCDs detect current leaking to earth and disconnect in milliseconds; a fuse does not, and that is the protection that prevents electrocution rather than just fire. A board of this type is the strongest single argument for an upgrade, and it is relatively inexpensive compared with a rewire.
Too few sockets
A house built for two sockets per room now runs a television, a router, chargers, a lamp and a games console off one double. The extension leads are the symptom. The problem is circuit capacity and socket provision, and adding sockets is covered separately — but it is worth doing as part of any other work rather than on its own.
The checks worth doing, in order
- Look at the consumer unit. Rewirable fuses or no RCD means an upgrade is the priority, ahead of almost anything else.
- Check the main earthing and bonding. There should be a substantial earth conductor at the meter position, and bonding conductors clamped to the incoming gas and water pipes close to where they enter. Missing bonding is common and is a safety fundamental.
- Take off one switch plate and one socket front. You are looking at cable colour and condition: modern brown and blue, older red and black, and whether the insulation is flexible or has gone hard. Turn the power off at the consumer unit first, or have an electrician do it.
- Look for an earth at the lighting switch, which tells you the era of the lighting circuit.
- Count the sockets and note where extension leads are permanently in use.
- Look for signs of partial work — a modern socket on an old circuit, a kitchen rewired alone, a new board on old cable.
- Get an EICR. It is the only way to know the condition of what is buried in the walls, and it produces a coded report rather than an opinion.
Steps one and two are visual and take five minutes. They also identify the two cheapest, highest-value improvements in most older houses, which is why they come first.
Why one house contains four eras
Older houses are rarely a single installation. They are layers: the original wiring, a partial rewire when a kitchen was fitted, a shower circuit added in the 1990s, a new consumer unit put on in 2010 without the cable behind it being touched.
That matters for two reasons.
A new consumer unit does not mean a rewired house. It is entirely possible to have a modern board with RCBOs feeding 1950s rubber cable. The board is the visible part and the cable is not, so the installation can look recent and be nothing of the kind. An EICR tests the circuits, not just the board.
Partial work creates odd combinations. A circuit extended from an old one inherits its limitations, so a brand-new socket can sit on a circuit with no RCD and degraded insulation. Borrowed neutrals — where a circuit takes its neutral from a different circuit, usually from two-way lighting altered over the years — are a classic result, and they cause RCDs to trip in ways that look inexplicable.
This is why deciding between a full and a partial rewire depends on what an inspection finds rather than on the age of the house. Two houses built the same year can need completely different work.
Mistakes Coventry homeowners keep making
- Assuming a new consumer unit means new wiring. It very often does not.
- Fitting metal switches and sockets on a lighting circuit with no earth.
- Decorating and flooring before rewiring, which means lifting both again.
- Treating age as the test. A sound 1980s installation can be fine; a neglected 1990s one may not be.
- Ignoring missing bonding because it is invisible and nothing has gone wrong yet.
- Leaving old cable live at one end after a partial rewire, instead of disconnecting it properly.
- Buying without an EICR on a house that has clearly not been rewired, then discovering the cost afterwards.
What it costs
These are the electrical figures published across this site:
| Job | Typical Coventry guide price | Notes |
|---|---|---|
| Electrician, hourly | £45–£90/hr | Certified, Part P |
| EICR (3-bed) | £150–£300 | Safety certificate |
| Consumer unit upgrade | £450–£700 | RCD protection |
| Full rewire (3-bed) | £3,000–£6,000 | Whole-house |
An EICR is the cheapest item on that list and the one that tells you whether you need the most expensive. On any older house that has not been inspected recently, it is the sensible first spend.
An EICR tells you the condition of the circuits rather than the age of the house, which is what actually decides the work.
Frequently asked questions
How do I know how old my wiring is?
Cable colour and condition give it away. Rubber or lead-sheathed cable is pre-1960s and past its life. Red and black PVC runs from the 1960s to 2004; brown and blue is later. Round-pin sockets mean nothing has been rewired on that circuit since the 1940s or 50s. An EICR confirms the condition.
Why is there no earth at my light switch?
Lighting circuits were routinely wired without an earth until the mid-1960s. The house works fine, but there is no path to earth for a metal switch plate or metal pendant — which is why an electrician will refuse to fit one. Take off a switch plate and look for a green and yellow conductor.
Does a new fuse board mean the house has been rewired?
No, and this catches a lot of people. A modern board with RCBOs can sit in front of 1950s rubber cable. The board is visible and the cable is not, so the installation can look recent and be nothing of the kind. An EICR tests the circuits rather than just the board.
Is aluminium wiring dangerous?
It needs attention rather than panic. Aluminium conductors appeared briefly in the 1970s when copper prices spiked. Aluminium creeps under pressure and oxidises, so terminations that were tight when made work loose over time, and a loose connection heats up. Terminations need checking by an electrician.
What is main bonding and why does it matter?
Conductors clamping the incoming gas and water pipes to the earthing system, so those metal services cannot become live at a dangerous voltage. It is a safety fundamental, it is inexpensive, and we find it missing or undersized in houses of every decade including recent ones.
Does an old house always need rewiring?
No. Age alone does not decide it — condition and earthing do. A sound 1980s PVC installation with a modern board may need nothing but an RCD upgrade. A neglected or heavily altered one of any age may need a great deal. The inspection is what tells you, not the build date.
Condition, not age
We start with the board, the bonding and an EICR, because those three tell you whether you are facing a small job or a rewire.