...and, if so, can it be located on a different wall?
I was asked today by a kitchen fitter. Here’s my answer…
The first thing to say on the matter is that there is no specific regulation in BS7671 requiring a cooker switch to be installed at all. Appendix H of the On-Site Guide says that a control switch should be supplied and located within two metres of the cooker and not directly above it, however this is just good advice and does not relate back to a specific regulation. The building regulations mention the same, but again this is given as guidance and not as a requirement. What they both do state is that it should not be mounted so that it is necessary to lean or reach over gas or electric hobs for their operation.
The wiring regulations do make mention of a ‘Cooker Control Unit Switch’ which, when compliant with BS4177, is considered suitable for isolation, emergency switching and functional switching (table 537.4).
As it can be used for emergency switching, other regulations apply including 537.3.3.6 which says “the means of operation shall be readily accessible at places where danger might occur”, and “Devices for emergency switching off shall be so placed as to be readily identifiable and convenient for the intended use”. Many would argue that a cooker switch would then have to be installed to comply with the requirements of Regulations under 537.3.3, but then you get Regulation 537.3.3.7 which states “The means of operation.... shall be capable of latching in the OFF position...”, and any cooker switch I’ve ever encountered lacks the ability to be directly locked off, although it does have the caveat of "...unless both the means and operation for emergency switching off and for re-energising are under the control of the same person".
Different people interpret certain regs in different ways because there are some grey areas where specifics aren’t given. Some would say that a cooker switch is unnecessary in the home because the circuit can be isolated from the consumer unit which, although not usually within two metres of the cooker, is still close by in your average abode. Others would insist a cooker switch is mandatory and the installation is not compliant without one. Here’s my take on it…
If you’re having a new kitchen, it is considered best practice for a cooker switch to be installed within two metres of the appliance, but not within 300mm of its hot surface and not directly above. If you need to shut the appliance off for whatever reason, that local source of isolation should be readily available.
Isolating at the consumer unit usually only disconnects the line wire; neutral remains connected unless you have a double-pole protective device. If your cooker has a neutral to earth fault that is causing an RCD to trip and take out other circuits, then the lack of a two-pole cooker switch will leave you requiring disconnection of either the circuit or the appliance in order to reset the RCD. This makes leaving out a switch harder for the installation to comply with Regulation 314 (Division of Installation).
Regulation 132.15.201, while not applying specifically to cookers, requires “Effective means [of isolation], suitably placed for ready operation… so that all voltage may be cut off from… all equipment, as may be necessary to prevent or remove danger”. The lack of local isolation switches for any fixed equipment such as a cooker, bathroom fan, shower, etc. would make it harder for the installation to comply with this requirement.
Although it’s not ideal, if you already have a kitchen where no cooker switch has been installed, you don’t need to fork out for one to be put in. It wasn't good practice for the installer to have omitted such, but there is no specific regulation insisting that one is mandatory.
If you have an Electrical Installation Condition Report performed on a property, then the electrical installation should not be failed for the lack of a readily available cooker switch. At worst it should be coded as a C3 (improvement recommended) under item 8.15 of the EICR checklist.
Hiding a cooker switch at the back of a cupboard or above kitchen units makes it not obvious or readily available to locate and isn’t good practice, however if a kitchen is small and lacks available wall space to accommodate a switch, then its better to have one than not, even if it is placed out of the way. It is recommended that wiring accessories of any kind should be mounted on the building fabric (i.e. screwed to the wall) and not fixed onto kitchen furniture. That said, the customer is king and sometimes they don't want the clutter of additional accessories in their eyeline.
If an existing kitchen is being remodelled and the cooker is moved to a new location, an existing cooker switch should be relocated to within two metres of the appliance but no closer than 300mm to the cooking surface. That said, if relocating the switch significantly adds to the complexity or costs of the job, and if the kitchen is a standard small domestic affair, and if the existing switch remains clear and accessible in its old position within the new layout, and if it can generally be reached and operated if required, then I personally wouldn’t go to the effort of shifting it. Every job has to be taken on its merits of course, but if I had to bust out someone’s ceiling to re-route the feed to a cooker switch that’s 3m away on the opposite wall of the kitchen to where the new cooker will be located, then I wouldn’t bother so long as it’s got a switch available and it's doing the job where it is. The two metre measurement guideline doesn’t mean that someone standing in front of a cooker can reach the switch in an emergency without moving. I can reach to about 90cm before I have to lean over or move my legs, so a switch located, say, 180cm away wouldn’t afford much difference to a switch located three metres away; you’ve still got to move your legs to get to it. The extra second it takes to get to that three metre switch won’t make much difference, even in an emergency. A cooker switch does not provide automatic disconnection of supply, that’s for your circuit breaker and/or RCD to do, so the switch isn’t there to protect from overload or electric shock. If the emergency is because your chip pan is on fire then that extra second, although not ideal, isn’t going to make much difference.
If you’re fitting out a new kitchen and are tempted to cut corners by leaving out a cooker switch, then you should bear in mind the get-out-of-jail regulation which covers the arse for BS7671:
Regulation 134.1.1 states “…The installation of electrical equipment shall take account of manufacturers’ instructions”…
…so if the cooker instruction manual says a double pole isolator must be installed, then not fitting one puts you foul of the regulations by the time you get to page 22 (and it’s a 560 page book!)
The bottom line
If you’re installing a new kitchen, fit one if there's space to accommodate it.
If you don’t have one, don’t worry, but plan to install one next time you remodel the kitchen if there's space to accommodate it.
If you’re remodelling an existing kitchen that lacks one, fit one where practical if possible, ideally within two metres of the appliance and not closer than 300mm.
If you’re remodelling an existing kitchen that has one and it's already within two metres of the appliance and it's not above the cooking surface, then you're golden, even if it is inside 300mm of the cooking surface.
If you’re remodelling an existing kitchen and the new cooker position won't be within two metres of an existing switch, evaluate the switch position and its accessibility with regard to the new layout and determine whether it's practical to relocate or better to leave as-is.
Regarding that last point, if you're a kitchen fitter or builder by trade who may come across this kind of situation often, then it may be worthwhile to prepare a risk assessment that you can apply and, if necessary, tweak for each job.
It should be borne in mind that the BS7671 Wiring Regulations are non-statutory so you don't have to comply completely, although it is of course best practice to do so and any non compliance should be detailed on the final certificate with justifiable reasoning for any deviations. As the designer of a kitchen, whether new or remodelled, it's up to you to use your judgement alongside the requirements of the regulations to decide what is going to work best in any given installation. In the event of an incident or accident you may be required to justify your design and/or installation work in a court of law, so your best defence is to make it as compliant with BS7671 as possible.
Personally, I've had to first-fix kitchen units so small that there simply isn't space for an isolator to be installed in a way that ticks all the boxes. I'm reminded of one small flat in particular whose kitchen was the size of a shoebox and lacked any available wall space. As the consumer unit was about three metres away down the hall, I installed a double-pole RCBO which allowed for isolation of the appliance in a way that best suited the circumstances. When Curry's later came out to install the cooker, they refused because there wasn't a cooker switch local to the kitchen which left us arguing over the phone, me pointing out there was two-pole isolation present, the moron from Curry's insisting it was their company policy to not proceed unless there was a red switch they could flick. Eventually, they got told by the customer to piss off and I came over to plumb the thing in. Mind you, my experience of Curry's cooker installers is that they'll find ten reasons why the job can't be done.
Remember folks, this is just my interpretation of the regulations and others will have their own opinions, but anyone who insists on a particular stance to the original question should be able to back it up. That is to say, if someone is telling you that you must have your kitchen busted out because the installer omitted a cooker switch or put it in the wrong place, don't just take their word for it, get them to prove their argument by digging out the specific wiring or building regulation which says it's necessary. They won't find one.
Postscript
This article was updated in January 2022 to reflect changes between 17th Edition Amendment 3 in force when originally authored and 18th Edition. The facts of the issue remain the same, but regulations, tables and page numbers have moved around. My thanks to Max at MB Installations for highlighting it being out of date.
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