The consumer unit, still called the fuse box or fuse board in most homes, is the part of your electrics that cuts the power when something goes wrong. In Derby, a consumer unit upgrade starts from £650 plus VAT. Here is what moves the price, what the job involves and how to tell whether yours needs replacing.
That price includes a new metal consumer unit, individual RCBO protection for each circuit, surge protection (SPD), full electrical testing, an Electrical Installation Certificate and Part P notification to Building Control. It assumes your existing installation is safe and suitable for the upgrade. Any extra work is quoted separately.
You get a free written quote before any work starts.
What affects the cost of a new consumer unit
Most of the difference between quotes comes down to a few things:
- The number of circuits. A larger house with more circuits needs a bigger unit and more protective devices.
- The type of protection. An RCBO on every circuit costs more than a split-load unit, but one fault will not take out half the house. We fit RCBOs on every circuit as standard.
- Surge protection. A surge protection device protects electronics and appliances. We include one as standard.
- The condition of the existing wiring. Faults found during testing have to be put right before the new unit can be certified.
- Earthing and bonding. Older homes often need the main earth or the bonding to gas and water upgrading at the same time.
We check all of this before quoting, so the figure you get is for your house and not a guess.
Signs your consumer unit needs replacing
Not every old unit has to go, but these are the usual reasons to change one. Not sure about yours? Our fuse box checker gives you a plain answer in five quick taps.
- It has rewireable fuses, with fuse wire, instead of switches.
- There is no RCD protection, so nothing trips if someone touches a live part.
- The casing is plastic or wooden, or shows signs of heat damage or scorching.
- It trips often, or there is no room left for a new circuit such as an EV charger or a cooker.
- An EICR has flagged it with a C1 or C2 code.
If you are not sure, our guide to the signs of unsafe electrics covers what to look for around the rest of the house.
What the job involves
We test the existing circuits first, so any problems are known before the old unit comes out.
The power is off for most of a working day while the new unit is fitted, connected and labelled.
Every circuit is then tested, and you get an Electrical Installation Certificate and Part P notification as standard.
How long does it take?
Most consumer unit upgrades in a typical house are done in a day. If testing shows faults on the existing wiring, we will tell you what they are and what they cost to fix before going any further.
Do you need an EICR first?
Not always, but it helps on older properties. An EICR is an inspection and test of the fixed wiring, and it shows whether a new consumer unit is enough or whether the wiring itself needs attention. Our EICR guide explains what it covers, and our guide to rewire costs in Derby covers the next step if the wiring has had its day.
Get a quote for a consumer unit upgrade
JJS Electrical Solutions is a NAPIT registered electrician based in Chaddesden, covering Derby and Derbyshire. Call 01332 492475 or send us a message for a free written quote.
We are rated 4.9 on Google by homeowners and businesses across Derby. See our guide prices for other common jobs.
