Often, yes. Old wired fuse boards, boards with one RCD for the whole house, and untested split load boards all give far less protection than a modern consumer unit with an RCBO on every circuit. If you have one of these, it is worth getting looked at, and an EICR (electrical safety check) will tell you.
It helps to know why. Here are the four boards we come across most often, and what each one means for you.
The old brown board with wired fuses
These boards are 40, 50 or 60 years old. The only protection is the fuse wire. On a socket circuit that is typically a 30 amp wire, which can carry well above 30 amps for a while before it goes, and it does not react to current leaking through a person or to earth.
A modern board has 30 mA RCD protection, which BS 7671 requires, that cuts the supply within a fraction of a second when current leaks to earth. That greatly reduces the risk of a fatal shock. It is not a guarantee, and you can still get a nasty shock.
These boards were also designed for a time when a bedroom had one socket. We didn’t have the appliances we have now.
One RCD that takes everything out
A board 30 or 40 years old with a single RCD (residual current device, the switch that trips when current leaks to earth) will often cut every light and socket when there’s a fault anywhere.
A modern board has an RCBO on each circuit. That’s a single switch that combines overload and earth leakage protection, so a fault on one circuit doesn’t take out the rest. A fault on the lighting circuit turns the lights off and nothing else. A fault in the kitchen turns the kitchen off. The rest of the house stays on.
Split load boards
Again, usually 30 or 40 years old and usually plastic. One RCD covers half the circuits, and the lighting is often left without RCD protection. A fault on the lighting could overheat before the breaker or fuse trips. BS 7671 requires lighting circuits in homes to have 30 mA RCD protection now.
If the board has never been tested, you can’t be sure the RCD still works. You might think you’re protected when you’re not. Press the RCD test button every few months, and an EICR tests it properly.
Plastic boards
Older boards were often metal, then plastic took over. Since 1 January 2016, BS 7671 has required consumer units in homes to have a non combustible enclosure (in practice steel), or sit in a non combustible cabinet. This came in with 17th Edition Amendment 3 (2015). It applies to new installs and replacements. It is not retrospective, so an existing plastic board does not have to come out just for that.
Is it worth replacing a board just to get a metal one? Not usually. But you’ll rarely find a plastic board with an RCBO on every circuit, and that alone is worth the upgrade.
If you let a property in England, landlords must have the electrics inspected at least every five years and fix any faults the report lists, under the Electrical Safety Standards in the Private Rented Sector (England) Regulations 2020.
Is it worth the money?
A new consumer unit isn’t cheap, and there’s nothing glamorous about it. Electricians get excited about a neat board. Most homeowners don’t. But your house is likely the biggest thing you own, and it has your family in it. We think it’s money well spent.
See our electrical services page for consumer unit upgrades and EICRs.
FAQ
Is a wired fuse board safe?
It gives very little protection against shock. A modern board with 30 mA RCD protection switches off far faster.
Why does all my power go off when one thing trips?
You probably have one RCD covering everything. With an RCBO on each circuit, only the faulty circuit switches off.
Should I replace a plastic consumer unit just to get a metal one?
Not on its own. But most plastic boards don’t have an RCBO on every circuit, and that is worth upgrading for. The metal case rule is not retrospective.
We’re NAPIT registered. Our work comes with a 6 year insurance backed workmanship guarantee, in addition to your legal rights.
If you’d like us to look at your board, book a visit here.
Related reading: our earlier post, Should I change my fuse box? (2023).
Jason Pope, Owner, Selec Group