Nine Times 'Just' Cost Someone a Full Rewire

There is a word that gets used in almost every enquiry we take, and it is doing an enormous amount of quiet damage. The word is 'just'.

Just a socket. Just move a light. Just swap the shower over. It's an entirely reasonable thing to say — you're describing the bit you can see and the bit you care about. The trouble is that the bit you can see is about ten per cent of the job, and the other ninety per cent is where the word 'just' goes to die.

Here are nine classics. Not to put you off. To help you ask better questions, spot a decent quote when you see one, and understand why the cheapest number on the list often isn't a bargain.

1. 'Just add a double socket'

Straightforward? Only if the circuit can take it. In a ring final you're normally taking a spur, which comes with its own rules. In a radial, spare capacity may not exist. Then there's the small matter of whether the existing circuit has RCD protection, whether the wall you've chosen is in a permitted cable zone, and what's behind the plasterboard.

What a good electrician checks: circuit type, cable size, existing load, RCD/RCBO protection, the route, and whether the socket will end up in a safe zone or on the surface.

2. 'Just move that light switch six inches along'

The switch is in a different place. Great. Now: is it a switch drop from the ceiling, and if so, is the wall you want it on a stud wall you can fish through, or solid brick you'll be chasing? Is it in a wet zone, near a shower or a sink? And plastering — is that included, or is that a separate trade coming next Tuesday?

3. 'Just swap the shower — the new one's a bit more powerful'

This one has ended more projects than any other. Going from an 8.5kW to a 10.5kW unit changes the current draw meaningfully, and the cable size, protective device and isolator all need to match. Sometimes the existing cable is fine. Sometimes it's 6mm when it needs 10mm, or run through a loft full of insulation. Sometimes the cable run is the reason the job suddenly costs four figures.

4. 'Just put a bigger fuse in, it keeps tripping'

No. Genuinely, no. A breaker tripping is information. Uprating it because the circuit keeps failing removes your protection and leaves you with a cable that is now the weak point. If a circuit trips, you find the fault — you don't shout at the safety device until it stops complaining.

5. 'Just swap the consumer unit before we sell'

A consumer unit isn't a plug-in accessory. Replacing it means testing every circuit first, because you can't meaningfully certify circuits you haven't checked. Occasionally that uncovers ring continuity faults, borrowed neutrals, or a lighting circuit with no earth. All fixable — none of it 'just'.

6. 'Just change the halogen downlights for LEDs'

Warm and straightforward, usually. But: older fittings often have transformers that don't like LED loads, some are dimmed on incompatible systems, some sit in insulation, and some have a habit of failing as soon as you disturb them. Nine fittings out of ten are fine. The tenth is why we quote a range.

7. 'Just a quick outdoor socket for the mower'

Outside sockets need RCD protection, an appropriate IP rating, and a cable route that isn't a black flex trailing through a hedge. Add a hot tub or a garden office and it stops being an outdoor socket and starts being a new circuit, which means design, notification and a proper protective device.

8. 'Just a socket behind the telly'

The wall's already decorated, the fireplace is a foot to the left, and nobody wants to know what's inside the chimney breast at this point in the conversation.

9. 'Just a new induction hob'

Induction hobs pull serious current, often on a dedicated circuit that has to be sized correctly and isolated properly. Add a cooker hood and an oven in the same run and you're doing load calculations, not swapping a plug.

How to spot a suspiciously cheap quote

A quote that arrives in ninety seconds and consists of one number is a wish, not a quote. Look for:

• Itemised labour and materials, or at least a breakdown of what's included.
• A stated assumption — 'assuming existing 2.5mm ring can accommodate a spur on RCD'. That sentence is a good sign, not a bad one.
• Notification under Part P where the work requires it, and a certificate at the end. If it's not mentioned, ask.
• Testing before work starts on anything involving the consumer unit or a new circuit.
• A caveat about what happens if the wiring behind the plaster isn't as expected — because it might not be, and you don't want that conversation to happen after the plaster comes off.

The cheapest quote is not always dishonest. But an unrealistically low one has to become realistic somehow, usually by leaving things out, skipping the test certificate, or discovering a problem halfway through when you've already committed.

Nine jobs, one lesson

The lesson is simple: an electrician isn't pricing the socket. They're pricing the unknowns between the socket and the consumer unit, plus the responsibility for making it safe. A quote that glosses over the unknowns isn't saving you money — it's postponing the bill until you're already committed.

Ask what they'd check. Ask what would change the price. Ask what certificate you'll get. A good electrician will happily answer all three, and it'll take them about thirty seconds.

Anything involving a consumer unit, a new circuit or a bathroom is not a DIY job in the UK. If you're unsure whether your work needs notifying, ask a registered electrician before you start — it's a much shorter conversation now than later.