Consumer Units For Use In Domestic (Household) Premises - The Impact Of Amendment No.3 To BS7671

By Chris Dodds on 1st June, 2015

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Consumer Units For Use In Domestic (Household) Premises - The Impact Of Amendment No.3 To BS7671

In the following Guest Blog we discover the impact of Amendment No.3 to BS7671 on both the electrical contracting and manufacturing industry in the UK.

We focus particularly on the changes to the 17th Edition Wiring Regulations and their affect on the selection and installation of Domestic Household Consumer Units.

Due to the significant increase in household fires caused by consumer units, as the point of ignition due mainly to poor installation, Amendment 3 now requires consumer units for use in domestic (household) installations to be manufactured from non-combustible materials. 


Representing the manufacturing sector is Wylex, the market leader in residential circuit protection, with the largest range of consumer units and RCDs in the UK. 

M-Spec ServicesThe voice of the electrical contractor is soundly represented by Michael Halverson, owner of M-Spec Services Electrical Contractors.  

M-Spec are a team of qualified and professional electricians based in Essex, UK - their electrical teams are IET Certified & Part-P for Domestic, Commercial and Industrial installations. On-call 24/7 service is available for domestic and commercial electrical installations and modifications.

Firstly, lets provide some background and context to the recent Regulation amendments.


When was Amendment No.3 Introduced ? 

From January 2015 Amendment No. 3 to BS 7671 IET Wiring Regulations prescribe that within domestic (household) premises, consumer units and similar switchgear assemblies shall have their enclosures manufactured from non combustible material, or be enclosed in a cabinet or enclosure constructed of non combustible material and comply with product standard BS EN 61439-3. 

What are Domestic Household Premises ?

Typical Domestic household premises would include single and multiple occupancy homes such as Houses, Bungalows, High Rise & Low Rise Flats, Apartments, Student lets, Sheltered Accommodation, Farmhouses, Houseboats, Static Homes, Home Office, attached Garages, Workshops and Detached Summerhouses etc.

Other types of building you may need to consider (these may be commercial ventures) but also where people live and guests sleep overnight such as Guest Houses, Hostels, Bed & Breakfast Accommodation, Nursing Homes etc.

Pictured : Typical Domestic Household Application With Meter Cabinets



  • What is Non Combustible Material ?

There are many types of non combustible material however, amendment 3 of the 17th Edition regulations provides an acceptable example as ferrous metal i.e. Steel Consumer Units.


  • What is an Enclosure ?

The consumer unit enclosure must be manufactured from a non combustible material so as to limit the spread of fire. An enclosure means the box, cover, door, hinges, handle and any components required to maintain the integrity of the unit.


  • What is Similar Switchgear ?

Similar switchgear is switchgear that is used for the same fundamental application ie. a circuit protection assembly with two pole isolator and one or more circuit protection devices, e.g. fuse switch, garage unit or PV switchgear etc.


  • What are Cabinets ?

Typical cabinets are meter cabinets that are normally built into the fabric of the building and that may or may not include consumer units within. If the cabinet is of an all metal construction (non-combustible), then a standard skeleton consumer unit (FAL) can be installed within. If the cabinet is of a combustible material, a metal consumer unit is required.

Yes it's very important that any customer checks all credentials of a electrical contractor and previous work and documentation but we all know this rarely happens ie client doesn't ask though Wylex are very clear with any clients on this subject.

This leads us on nicely to the importance of workmanship and the need to weed out sub-standard installations.


  • Regulation v Professionalisation of the Electrical Industry


Pictured : Shoddy Workmanship. Cowboy Builder Charged £49,000 To Turn Our Home Into A Deathtrap. 

One light switch turned on a lightbulb elsewhere in the home. Image : Daily Mail.


Is Amendment 3 just more red tape contrived by vested interests to fatten profits or a genuine drive towards protecting our homes and families against household fires? Discuss.

Whichever side of the argument you align yourself to presumably the end outcome should be a reduction in domestic fires. Perhaps not.

Tune into the Wylex video below and listen carefully to the opening sentence. The new BS7671 Regulations were a response to the significant increase in house fires caused by consumer units as a result of, wait for it, "mainly poor installation". 

Presumably then good quality consumer units installed by Qualified and Trained electricians would not present potential ignition hazards?

Yes, in an ideal world. But not all electricians are actually qualified and suitably trained. Really? Yes, really....


  • What's Lurking Under The Stairs?

The debate rages on in the electrical contracting industry and across social media land. Go to Twitter and everyday you will see examples by Mike and his "Band of Brothers" of pardon the pun, shocking electrical work. One sure thing is anyone considering employing an electrician to carry out work on their home should check the professionalism of the contractor. Don't take their word for it.


  • Dodging The Dodgy TradesmenNICEIC

Turn to the back pages of the free newspapers that drop through the letterbox.

Scan the classified Ads. 

Beware of vague unsubstantiated claims of legitimacy. "All work undertaken", "fully insured", "fully approved.

How does Joe or Joanne Public know whether all these apparently "qualified" electricians, plumbers and builders are actually what they claim to be? 

Look for their business address, their website, a company registration number or the logo of an industry recognised scheme of approval.

For instance, the NICEIC aims to protect everyone who uses electricity from unsafe electrical installations anywhere. Ask your electrician if they are NICEIC Approved.

The NICEIC maintain a register of qualified, competent electricians and have been assessing the technical competence of electricians for over 50 years. 

Competent electricians such as M-Spec Services, proud NICEIC badge-wearers.

Mike at M-Spec corroborates the link between household fires and "cowboy" installs, "I have friends that are firemen and we all understand totally the reasoning for the introduction of Amendment 3. But it's because there are so many un-skilled and under-trained 5 week wonders out there not installing consumer units correctly. We now have plumbers turning their hands to cabling and worse still week-end DIY'ers attempting household electrics which should only ever be carried out by qualified and trained electricians."

"Wylex manufacture good, solid and reliable Consumer Units which are fairly easy to install unlike some on the market. Furthermore, the low smoke and fume paint coating is an additional safety measure should the worst happen".

Hopefully, the installer-friendly design and advanced specification of Wylex consumer units should reduce household fires. One fact is that poorly designed units installed by pseudo-electricians could literally be fuelling the fire whatever the Regulations say.


  • Mike at M-Spec, Mainstream or Maverick?

We'd be interested to receive Comments on this topic to add to the post. Submit to and we will moderate for possible inclusion. Is Mike a lone-wolf or thought-leader? Get in touch and let us know what you think. 


The 3rd Amendment Website  

BS7671 3rd Amendment



Video : Wylex NM Amendment 3 Consumer Units. 

New wiring regulation, New consumer units - Features :

  • All metal enclosure, no external plastic parts
  • Low Smoke & Fume paint
  • Non combustible cover blanks
  • Compact enclosure
  • Available in ‘no miss terminal’ fixed busbar versions and flexible versions
  • Raised & removable DIN rail / busbar assembly
  • Cable entry knockouts on 5 sides, top, bottom, left, right and rear
  • Up to 38 way units, designs Main Switch, High Integrity, Split Load, Dual RCD
  • RoHS compliant in excess of UK standards. UKAS certified to BS EN 61439-3


Wylex : The clear market leader in residential circuit protection, with the largest range of consumer units and RCDs in theWylex UK. This gives designers and installers the flexibility to create an almost infinite variety of systems, tailored to individual applications and blending with any surroundings. Easy nationwide availability adds to convenience whenever Wylex is specified.
More Contractor Talk...

Amendment No.3 BS7671 & Consumer Units For Use In Domestic (Household) Premises - Wylex Consumer

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