Advised to change plastic consumer unit

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I am in the process of having electric certificates carried out on rental properties. The quote has stated that all plastic consumer units must be changed for metal enclosures. Ive read the electrical regs they do not state that they must be changed, and plastic consumer units are still being sold by everyone at all points. Can someone please straighten out my thoughts on this as the costs of replacing them seem so very high to me. Any help would be appreciated.
 
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It's not compulsory - but you are a landlord and so it is deemed necessary that you do everything possible to bring the property up to the latest regulations for everything otherwise it shows you don't care about your tenants..
 
Thanks for your prompt reply, I consider myself very conscientious about my properties and the tenants wellfair, but, why earth are they still selling plastic cu if they are not deemed safe for tenants then they are not safe for anyone. As you rightly point out it is advised where problems could arise. If the installation is if and working well in all other aspects that was my concern, as to replace the boxes I’m being quoted up to a thousand pounds fir some that should take no long than an hour for each. I understand the process as I was trained initially as an electrical engineer but obviously at this point can’t sign these things off and want it done properly
 
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Screw fix, edmondson, cef, almost every electrical wholesaler I have checked with
 
These are the first 100 consumer units at Screwfix. All metal, apart from a couple of 2 module enclosures designed for a single RCD or isolator.

CEF have a few plastic ones available, all of which are in the 'clearance' category.

The requirement for them to be 'non-combustible' (which for practical purposes means steel), was introduced 8 years ago.
There are still some situations where plastic ones can be used, but as most consumer units are installed in homes, the vast majority of consumer units have been metal for years.
 
Thanks very much for all your input, it is all taken on board and I will as you suggest go with the metal ones as I consider this the appropriate action. Once again thank you all for your help it’s really appreciated
 
The requirement for them to be 'non-combustible' (which for practical purposes means steel), was introduced 8 years ago.
For the benefit of Peterpies, the "offending" regulation is :
421.1.201 Within domestic (household) premises, consumer units and similar switchgear assemblies shall comply with BS EN 61439-3 and shall:
(i) have their enclosure manufactured from non-combustible material, or
(ii) be enclosed in a cabinet or enclosure constructed of non-combustible material and complying with Regulation 132.12.

Which as you may note, does not say what is considered non-combustible. There are standards for assessing combustibility, but the committee that writes BS7671 decided (for whatever reason) not to reference any of them. If you've ever seen video of an oxygen lance being used to dismantle even reinforced concrete, you'll realise that given the right (or wrong) conditions most things are combustible.
However, the authors added a note :
NOTE: Ferrous metal, e.g. steel, is deemed to be an example of a non-combustible material.
So despite steel being very much combustible if you apply enough heat and oxygen, they've said it is considered non-combustible and hence it's OK to use it. Hence why Flameport says "which for practical purposes means steel".

Many plastics are, by the tests used in many standards, also non-combustible - but because the regulations is so badly written, there's no objective way to say that anything other than steel is compliant. I would think that most of the decent brand CUs will have been made of flame retardant plastics and in practice pose little risk.
The risk is, BTW, that when there's a fault (such as a loose connection where the meter tails connect to the main switch), heat can be generated, and that can cause the plastic to burn. It is a widely held view that the regulation was put in to satisfy those well known electrical experts, the London Fire Service, who observed a rise in domestic fires which originated at the consumer unit - but chose to get this regualtion added rather than tackling the poor workmanship of meter fitters disturbing the meter tails while fitting "smart" meters and not properly checking the terminals for tightness afterwards.

Needless to say, there was "some disquiet" from people being told that their newly fitted consumer unit - perhaps upgraded to meet rules on RCD provision - was now "unsafe" and needs replacing again. Not to mention, that there would not have been enough electrician around to have replaced them in a timely manner.
And, as will be of interest to yourself as a landlord, we come to EICR time. There was "some debate" in the industry as to how a plastic CU case should be coded - with opinions and arguments for anything from a C2, through C3, to not coded at all. I had an email exchange with someone from the standards committee who advised that a pragmatic approach would be to code C3 where the CU was under wooden (i.e. combustible) stairs or in an escape route, and to not mention otherwise. However, despite phrasing things as if this was the view of the committee, he would not commit to anything more than this being his personal opinion.

If you are now thinking this is a somewhat unsatisfactory state of affairs, you are far from alone. The committee cannot not realise this - I'm sure I am not the only one who has raised this with them. Yet they have failed to improve things in the (IIRC) at least 2 updates since this regulation was introduced.

So where does this leave you ?
If your inspector is telling you that you "must" replace the CUs, then I would suggest they are being a little dishonest - bear in mind that many unscrupulous people use EICRs as a means of generating work, and offer inflated quotes for it. This is not helped by knowing that they can code a C2 for a landlord and then the clock starts ticking on the 28 days in which the landlord must rectify it. If they are saying it's a C2 then they are most likely in this category.
So, assuming you have a more honest inspector, then it may be coded as a C3. You do not have to fix these, it is up to you to work out the risks and benefits.
I see two risks :
One is that there is a fire, and someone blames the plastic CU for it - and by implication, you for not replacing it. But a plastic CU will not catch fire all by itself, there needs to be a fault to generate heat. Simple maintenance (checking all terminals for tightness), which (for me) would be part of a routine EICR will deal with most of those anyway. Also, the location of the CU will have a significant impact on the severity of the risk - if it's not where it would impede evacuation after all the smoke alarms go off, then there's not really any risk is there ?
The other is the "professional chancer" tenant - the sort that knows the rules inside out and will use any excuse to try and extort money out of you or justify not paying the rent. Not been there myself, but I'm sure some of them would use the presence of a C3 in the EICR as justification as to why the property is dangerous.

As an alternative, do note the (ii) above "be enclosed in a cabinet or enclosure constructed of ..." Plasterboard is accepted in the building industry as non-combustible, so one option could be to fully line a cupboard containing the CU with that - and ensure it has a good catch to hold the door shut.

But really each installation needs to be considered on it's own merits.
 
@SimonH2 has given chapter and verse, there were some MCB's where the terminal screw when slacked off did not draw the clamps open, so it could be inserted on the bus bar with the bar wrong side of the clamp, so it only pressed against the bus bar it was not firmly clamped, the result was a poor connection which over time could heat up, basic poor design, it was OK when the MCB's were fitted on the bench, but once on the wall hard to ensure clamped correctly as the DIN rail did not allow one to test if firm.

I personally think this was the reason for the fires, however not proved.

As to BS 7671 each edition gives a date at which designs must apply, so they are not retrospective. So if it complied in 1992 when BS 7671 came out, it still complies, however things have moved on, LED lights, inverter drives, etc, so needs have also changed, like type of RCD used, and SPD so the inspector who writes the EICR no longer has code 4 which was does not comply with current edition of BS 7671, but the inspector is given a free hand as to what he feels is dangerous or potentially dangerous, and 230 volt is always potentially dangerous so hard to ever say he is wrong. Although if at any time BS 7671 did permit it, then most would only give a code C3 which is Improvement Recommended.

The EICR is only as name implied about the electrics, so only concerned with the installation, the only current using appliance considered as part of the installation is the lights, although the English landlord law includes any appliance not readily moved, these are covered by the inspection and testing of in service electrical equipment normally called PAT testing. Some equipment does need special tools, like microwaves to check leakage, and smoke alarms which need a smoke generator so just as well they are not covered by the EICR and items like the boiler often needs some one who is classed as gas safe to remove covers, but the law seems to have glossed over that, so an EICR is not always testing what it really should to comply with the law.

So when the fire inspection is done, the fire brigade could high light missing smoke alarms, plastic consumer units etc, which if done after the faults listed on the EICR are corrected then rather a pain to be high lighted then, so many inspectors will include these items even if not strictly part of their remit, a damaged smoke alarm with exposed wiring is part of the EICR but missing is not, even if the regulations say they must be installed.

I know where I live in Wales there is an acute shortage of houses to rent, many landlords have said enough is enough, and got out of the house market, and gone into mobile homes, as the regulations are not as strict. Which includes the extra charges if not occupied for the set number of days per year not to be charged extra tax.
 
Code 3 (so still satisfactory), for plastic consumer units showing no signs of thermal damage.

Only a Code 2 (unsatisfactory)if signs of thermal damage.

I didn't read all the above replies, so sorry if I repeated anything, I'm not normally a copy cat.
 
I wonder if, anyone on the regs committee has been monitoring the incidence of CU fires (including LFBs data) since the new reg's introduction?

The number of CU fires would surely be the same, but their spread should have been limited due to the reg change.
 
I sent pic of my plastic consumer unit to an EICR assessor. He said it will not be a fail. The internet says there is no retrospective regs. If the unit is not faulty, it doesn't need replacing.
 
I think the reg is terriblly written.

But IMO the real issue with thermoplastic enclosures is that regardless of how combustible they are, they do a poor job of maintaining their integrity during thermal events.

Put this together with the poor busbar design, the use of high current single phase supplies in the UK, and the fact that CUs are likely to be in a "cupboard under the stairs" and you have a recipe for problems.
 

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