From summer 2015 it might start to get more expensive....


In January 2015, IEE Wiring Regulations (BS7671) Amendment 3 will be published. A major change in Amendment 3 concerns consumer units, the term for a modern day domestic fuse box. New regulation 421.1.201 will state that in domestic environments, consumer units and similar switchgear must be constructed from non-combustible material.

regulations amendment 3


Most domestic consumer units you would buy from a retailer at the time of writing would be made of plastic. Although this plastic is glow-wire tested to at least 660 degrees Celsius, the London Fire Brigade have found in testing that an electrical fire breaking out within such an enclosure due to poor wiring terminations can lead to a fire which is able to deform or destroy the enclosure. They also found variations between manufacturers with some products offering better performance in a fire situation than others as a result of the presence, or lack thereof, of flame retardants in the plastic.


Obviously this can lead to further spreading of the fire, and as many consumer units happen to be installed under the stairs or by the front door within dwellings, then it can result in escape routes becoming impassable though flames, heat and/or smoke.


The impact of regulation 421.1.201 will be that domestic consumer units installed in the future will likely need to be made of metal or encased within a metal enclosure.


Amendment 3 comes into effect on 1st July 2015, however compliance with regulation 421.1.201 will not be mandatory until January 2016 in order to allow consumer unit manufacturers to retool their production lines and for suppliers to shift the existing stocks of plastic enclosures in their supply chain.


At the moment it generally costs more to purchase metal enclosures, although the costs are expected to drop through economies of scale once all manufacturers have retooled and switched from plastic, however installing a metal enclosure will likely be more time consuming and less convenient for your chosen sparkie, therefore it may be the case that the average cost for a consumer unit change increases from summer 2015.


If you’re planning on upgrading an old fuse box or consumer unit, here are some things you need to consider...


Don’t be afraid of plastic consumer units if you already have one or plan to have one installed in the coming months. So long as they’re installed properly and not tampered with afterwards, plastic units are just fine.*


If having your fuse box/consumer unit upgraded, make sure you select a proper registered, reputable electrical installer and that their work is certified afterwards. As I said in another article, your protective devices are there to keep you and your electrical installation safe, so don’t trust such important work to cash-in-hand cowboys, generic builders/handymen, well meaning family/friends or anyone else who isn’t going to leave you with signed certificates to say the job was done properly, complies with all wiring & building regulations and they accept the liability.


Whether or not your current fuse box or consumer unit is located in an escape route, if you’re worried about its suitability for continued use because it’s old, damaged or may not have been installed or maintained by a professional, then book an Electrical Installation Condition Report from a reputable firm. A full inspection and test of the entire electrical installation at your property will highlight any issues, or will give you peace of mind that there is nothing to be worrying about!


Beware of shops or suppliers selling off plastic enclosures at discount rates between now and 2016. If you buy one yourself, you may struggle to find a sparkie who is willing to install and certify it, especially after the summer 2015 implementation date or January 2016 deadline.


If you’re happy to have a plastic enclosure, especially because it’s going to be in a garage or outbuilding and not located in any escape route anyway, it may be best to arrange for installation before the risk of price rises from summer 2015. Similarly, if you’ve already bought a plastic consumer unit and you’re looking for someone to install it, make arrangements sooner rather than later or you may find yourself stuck with an item you can never use.


Only time will tell what the changes mean to pricing, and things will be clearer once the new domestic market metal consumer units start entering the supply chain in place of their plastic predecessors, but if an upgrade has been something you've been meaning to get around to for some time then booking early may save you a few pounds, especially if the prices of plastic enclosures drops as suppliers and installers work to clear inventory from their shelves.

More information on London Fire Brigade's testing can be found here.

*An updated article from April 2016 regarding whether a plastic CU should be upgraded to a metal unit can be found here.