Metal v Plastic fuse-box rental

PoGee

I'm sure my 1st property (now a rental) had a metallic fuse box which was changed to plastic for 'safety reasons'. My letting agent says it now needs to be a metal one (!) but when I contacted a landlord helpline, they said - no, as long as there is no damage to it. There is no damage.

I'd like to get a health check done on it anyway but I'm surprised at just how many electricians say on their websites that a metallic consumer unit is now mandatory.

Will an electrician come out to just do a health check on it or would they think it was too small a job? How much would they charge? 

bjorn_toby_wilde

I believe metal ones are being fitted in all new builds and extensions now but it’s not mandatory to retrofit them to existing properties.

We had a kitchen diner extension five years back and as part of the electrician’s work he installed a mains heat alarm in the kitchen and linked mains smoke alarms in the hall and landing as well as changing the consumer unit for a new metal one. That was to meet regulations as the kitchen diner was a “new installation”.

Albermarle

As above, metal ones are in the regulations for new installations. However ones with plastic cases are fine and will still pass an electrical safety check, assuming there is no other issues with them.

GDB2222

Any new installations have to meet current regs, which require a metal consumer unit.

As a landlord, you need an EICR, which lists any faults. If you have a plastic CU, the EICR should flag that as not to current regs. But the regs change pretty often, and it's entirely possible for an installation to be safe even though it doesn't meet the current regs.

EICR Fault Codes & Their Meanings

Code	Severity	Description	Examples
C1	Immediate Danger	Urgent risk of injury; requires immediate action	Exposed live wires, overheating connections, missing earthing
C2	Potential Danger	Not immediately hazardous but needs urgent attention	Damaged insulation, poor bonding, sockets near water
C3	Improvement Recommended	No danger, but safety could be improved	Lack of RCD protection, outdated fuse boards
FI	Further Investigation	Issue can't be fully assessed during inspection; needs deeper analysis	High resistance readings, unidentified components

PoGee

Thanks for replies. EICR was a couple of years ago, before the Scottish 2024 update in regs. A clear pass, no issues. All circuits have an RCD, 3 spare circuits.

GDB2222

PoGee said:

Thanks for replies. EICR was a couple of years ago, before the Scottish 2024 update in regs. A clear pass, no issues. All circuits have an RCD, 3 spare circuits.

I'm in England, and Scotland may be different, but here EICRs are generally valid for 5 years.

sheenas

Rather than replace the plastic consumer unit a metal one you can buy a maus firosticker which is a fire suppression device. It’s £35 rather than £1000ish and provides protection in the very unlikely event of a consumer unit fire. 

Ectophile

If the old one was a 1960's or earlier Wylex thing, then the fuse box would have been overdue for an upgrade.

For a few decades, plastic ones were standard.  But the manufacturers started to outsource the manufacturing to China, and they cut costs by leaving out the fire retardants.  The London Fire Brigade started seeing more and more house fires started by loose wires in fuse boxes.

After some lobbying, the 18th edition of the IET Wiring Regulations (aka BS7671:2018) had a rule that all domestic fuse boxes should be metal (with some exceptions or alternatives).  So no plastic ones should have been fitted inside a home since about 2019.

A rental property should have an up-to-date EICR with no C1 or C2 defects (that haven't been fixed).  A plastic fuse box in good condition with no signs of overheating may only get a C3.

PoGee

Ectophile said:

If the old one was a 1960's or earlier Wylex thing, then the fuse box would have been overdue for an upgrade.

For a few decades, plastic ones were standard.  But the manufacturers started to outsource the manufacturing to China, and they cut costs by leaving out the fire retardants.  The London Fire Brigade started seeing more and more house fires started by loose wires in fuse boxes.

After some lobbying, the 18th edition of the IET Wiring Regulations (aka BS7671:2018) had a rule that all domestic fuse boxes should be metal (with some exceptions or alternatives).  So no plastic ones should have been fitted inside a home since about 2019.

A rental property should have an up-to-date EICR with no C1 or C2 defects (that haven't been fixed).  A plastic fuse box in good condition with no signs of overheating may only get a C3.

New consumer unit with RCDs was fitted at end of 2013.
Yes it was on as a C3 - EICR (carried out by different electrician from 2025 electrician) was at end of 2023 with recommendation for repeat in 2028. Non electrician visual inspection shows no burn marks. 
I would have agreed to letting agent electrician doing works but they didn't say that it's notifiable works (saw that online), said would give a minor works letter (no EIC) and no mention of repeating eicr.