Adding cooker hood to a kitchen

[siimon]

Hi All,

The plan is basically:

Drop the ring main from upstairs, to a surface mounted socket just beside the hood, put a plug on the flexible cable that comes from the hood and fuse it appropriately. Note: there is no kitchen ring, the whole house has a single ring for pretty much everything besides the cooker and boiler. There are virtually no instructions with the hood besides a diagram on a label inside it.

Some questions:
1) Do I have to do something with bonding back to the CU, because that will mean pulling up a lot of floor boards as the CU is the other side of the house, and it's mid-terrace :-(. It seems there are three options for the earthing here:
- Take 10/16mm cable back to CU,
- Connect two 1.5mm wires from the socket to the hood (2 because it's a ring, I think?)
- Simply rely on the plug for earthing.

2) Is it OK to have my isolation in the form of a high-level socket next to the hood, or does that have to be accessible without standing on a chair? I've seen people having a switched fused spur just above the worktop, and then a switched socket next to the hood as well (two fuses, basically), but this seems overkill. I know that bathroom fan isolators are normally quite high up, but this would be high up and also reachable only by leaning over the hob - is it likely to be acceptable?

3) When I checked LA BC website it only seems to have a single form for any BC application, nothing specific to part P work. Is that normal, or does it vary by LA? Never done this before, so it would be nice to know what to expect, also would appreciate a hint about how much/what info I should be putting on the application. I understand that the response to the application seems to vary based on how much competency you display, so I want to try to understand what I'm on about before approaching them!

thanks,
Simon.

 

[Octopus]

4). Employ a sparky?

 

[telectrix]

^^^^^ seconded.

 

[siimon]

I answered my own questions:
1) No bonding needed on cooker hood as it's double-insulated and informed opinion says earthing a cooker hood may electrocute someone in the event of an earth fault elsewhere, so just a plug and lead on that.
2) I am going to go for 'yes'.
3) Dealing with my LA: That was a bit of a laugh...not. Eventually I spoke to someone who told me I needed to apply for a quote to have the work checked. They said it wouldn't be worth my while doing it myself because it would cost £500 for someone to spend an hour at the property checking it, something about insurance. I told them I'd already done the work and so I couldn't get someone else in. They told me some sparks might check it for me and sign it off, but I needed to ask around. I thought that kind of thing wasn't legal, and to have the BC actually suggest it seemed bizarre.

Anyhow, I was just about to start ringing round for quotes for the work to be done again, when I realised the law changed in 2013, and this is no longer notifiable. Nice.

 

[Leesparkykent]

I answered my own questions:
1) No bonding needed on cooker hood as it's double-insulated and informed opinion says earthing a cooker hood may electrocute someone in the event of an earth fault elsewhere, so just a plug and lead on that.
bonding a cooker hood? Did you really use 1.5mm cable? Did you confirm it's a ring? Did you actually carry out any testing before and after?
2) I am going to go for 'yes'.
3) Dealing with my LA: That was a bit of a laugh...not. Eventually I spoke to someone who told me I needed to apply for a quote to have the work checked. They said it wouldn't be worth my while doing it myself because it would cost £500 for someone to spend an hour at the property checking it, something about insurance. I told them I'd already done the work and so I couldn't get someone else in. They told me some sparks might check it for me and sign it off, but I needed to ask around. I thought that kind of thing wasn't legal, and to have the BC actually suggest it seemed bizarre
depends what CPS they are of....and if they are willing to I suppose
Anyhow, I was just about to start ringing round for quotes for the work to be done again, when I realised the law changed in 2013, and this is no longer notifiable. Nice.[/QUOTE
you seem proud about doing the work yourself and pleased about not having to get some one in to test it.........just because it works doesn't mean what you have done is right or even safe :wink5: [/QUOTE

 

[siimon]

I don't need to confirm it's a ring. What else would it be? Upstairs socket with two cables coming out below the floor, a CU with only five circuits, clearly labelled: Up/Down lights, cooker, immersion (single socket in cupboard), and single ring for the entire house.
Yes I am pleased with myself, or at least I will be until you tell me what I am doing is contravening either BS7671, the building regulations, or something on ---.gov.uk!
Testing is an interesting one. I'm going to just play devils advocate and tell you I won't be doing any testing. Can you then show me the relevant part of the regs that says I have to test, and what I have to test?
Yes, agreed, it's common sense to test as much as you can, but can you show me some facts in this regard?

Thanks!

 

[Octopus]

I don't need to confirm it's a ring. What else would it be? Upstairs socket with two cables coming out below the floor, a CU with only five circuits, clearly labelled: Up/Down lights, cooker, immersion (single socket in cupboard), and single ring for the entire house.
Yes I am pleased with myself, or at least I will be until you tell me what I am doing is contravening either BS7671, the building regulations, or something on ---.gov.uk!
Testing is an interesting one. I'm going to just play devils advocate and tell you I won't be doing any testing. Can you then show me the relevant part of the regs that says I have to test, and what I have to test?
Yes, agreed, it's common sense to test as much as you can, but can you show me some facts in this regard?

Thanks!

Try that last bit on your insurance company when you've had a fire caused by your electrical work!

 

[siimon]

Try that last bit on your insurance company when you've had a fire caused by your electrical work!

So no facts then, just hearsay. Who has actually had insurance refused as a result of DIY electrical work, and what kind of electrical work was it, and was it compliant with BS7671, if not how did it not comply, or are you just scaremongering?

 

[Octopus]

So no facts then, just hearsay. Who has actually had insurance refused as a result of DIY electrical work, and what kind of electrical work was it, and was it compliant with BS7671, if not how did it not comply, or are you just scaremongering?

Not going to argue with you as I don't want to descend to your level.

 

[siimon]

Not going to argue with you as I don't want to descend to your level.

Yes, it's a bit of a nuisance when people ask for facts and/or references to support the statements you're making in a discussion, but in your favour, rather than in a face-to-face discussion, this is over the internet, so you've Google at your disposal. All that I'm asking is that you refer to one of several billion documents indexed on the internet to support your claim. I'm not actually having a go, honest .

 

[Leesparkykent]

I don't need to confirm it's a ring. What else would it be? Upstairs socket with two cables coming out below the floor, a CU with only five circuits, clearly labelled: Up/Down lights, cooker, immersion (single socket in cupboard), and single ring for the entire house.
it could easily not be a ring, but you wouldn't know 100% as you haven't carried out any tests.
Yes I am pleased with myself, or at least I will be until you tell me what I am doing is contravening either BS7671, the building regulations, or something on ---.gov.uk!
by not testing the work you have carried out
Testing is an interesting one. I'm going to just play devils advocate and tell you I won't be doing any testing. Can you then show me the relevant part of the regs that says I have to test, and what I have to test?
Yes, agreed, it's common sense to test as much as you can, but can you show me some facts in this regard?
bs7671 and probably others without looking.
Thanks!

have you got an RCD? Are bonding and earthing arrangements adequate? Does your EFLI comply with the maximum permitted by bs7671? Does your RCD trip within permitted times (if you have one)? How do you know if there is any loose/broken connections on the ring (if it is a ring)? Insulation resistance?........

 

[siimon]

have you got an RCD? Are bonding and earthing arrangements adequate? Does your EFLI comply with the maximum permitted by bs7671? Does your RCD trip within permitted times (if you have one)? How do you know if there is any loose/broken connections on the ring (if it is a ring)? Insulation resistance?........

Now we are getting somewhere, some *information*. Thanks Leesparky kent.
I still want to know what is the regulation governing which tests are required for which kinds of alterations. I mean, the decorator yanks off all my sockets, and does no testing when he puts them back. Isn't he just as likely to mess something up as I am with my WAGO boxes?
Yes, I have RCD, it's 17th ed CU.
I think the bonding arrangements are adequate, due to following various discussions on this, some of them on this forum, but I welcome references to 7671 that tell me I've got it wrong. I am not bonding the cooker hood at all. Only the electrics inside it will be earthed via the plug, just like a fridge would be.
For EFLI can I test with MFT at the socket, when I do my RCD check, or do I need to pull the whole ring off. To be honest I didn't want to mess with the CU, and decouple the ring off it, but I can do. Again, I really want to see the rules that govern this, and say: You've changed --- therefore you need to test YYY, but 7671 doesn't seem to be clear on this, and is not an easy read.
RCD trip times, I've got a plug that came with the MFT and a mode that apears to test this.
Loose, broken connectors, how would you know? Undo them all and put them all back? Which ones? I did check the socket directly adjacent to my new one and it seemed sound.
Insulation resistance: Is it just the new 'leg' of the circuit that gets tested or does the whole ring need doing? Can I do all this without uncoupling from the CU?

 

[Darkwood]

Siimon - members are actively trying to help, bring attitude to the table helps no-one and only baits for negative response.

BS7671 - Chapter 61 Initial Verification

610.1 - Every installation shall, during erection and on completion before being put into service, be inspected and tested to verify, so far as is reasonably practicable, that the requirements of the regulations have been met. (Note! - only showing the relevent part of this clause, full regulation not shown).

Any alterations, additions or new work on any of your electrics requires by regulation to be tested and confirmed it meets requirements, not to do so may miss something that could ultimately in the worse case, kill someone or burn your house down.
Any competent Electrician would never consider doing any work without fully testing it, consider an RCD which is now required on most domestic circuits subject to install methods or if they are sockets.. you press the test button on it and it trips, this does not confirm it complies to regulation and will trip within specified times, it merely proves it mechanically operates when a leakage is introduced.

We as a forum are in a hard place when giving advice to DIY because any work like extra sockets, lights, new circuits all require testing and usually the DIYer has no test equipment to do such or an understanding of the results any test equipment may give if they did have access to some, also a lack of knowledge of compliant installation methods. We class DIY as changing switches, socket tops, light fittings etc which we are happy to help but where DIY extends to adding new, altering existing circuits etc then our advice is have your work done by, overseen or checked by a competent electrician, if you do not wish to take this advice then we can no longer help you. I ask kindly you do not start giving attitude because you do not receive the answers you want.

Just to add -

610-4 applies to additions and alterations and adds that your work complies with regulation and also that it doesn't impair the safety of the existing install.

610.5 - The verification shall be made by a skilled person, or persons, competent in such work

 

[Spoon]

Hi siimon. It may look like they guys on here are being a pain but what they are saying is for your own good.
I recently has an extractor fan added and a power socket moved in the kitchen. I could have easily done the job myself, but I don't have any calibrated test equipment and I also wanted the cert to say it had been fully tested. It didn't cost a lot and if there is a fire in the kitchen and the insurance people try and get out of paying due to I don't have the test certs then I am covered.

 

[siimon]

We class DIY as changing switches, socket tops, light fittings etc which we are happy to help

This doesn't seem to be the case as I can see from other posts on the forum.

First people say I don't know what I'm doing, but fail to tell me how my installation isn't compliant. Next they say I need test equipment. When I tell them I've got it, they fall back on telling me I don't know how to use it. If I did know how to use it, what would be the point in coming on this forum in the first place? It does seem as though I can't win, and perhaps that explains my frustration?

 

[siimon]

Hi siimon. It may look like they guys on here are being a pain but what they are saying is for your own good.
I recently has an extractor fan added and a power socket moved in the kitchen. I could have easily done the job myself, but I don't have any calibrated test equipment and I also wanted the cert to say it had been fully tested. It didn't cost a lot and if there is a fire in the kitchen and the insurance people try and get out of paying due to I don't have the test certs then I am covered.

I don't see why the insurance company would even be asking about the modification unless you volunteered the information. How would they know to go looking? Would they look in the charred remains for harmonised vs non-harmonised wiring? Even if they found them, how would they prove that the installation was not tested, and not installed by competent persons. You could have tested it with fully calibrated equipment and just discarded the results. I'm not aware of any law requiring you to keep these records for non-notifiable work. Please correct me if I'm wrong!

 

[Spoon]

Hi siimon. You don't seem to be seeing the picture....
Are you going to fill in your own cert?

 

[Octopus]

I don't see why the insurance company would even be asking about the modification unless you volunteered the information. How would they know to go looking? Would they look in the charred remains for harmonised vs non-harmonised wiring? Even if they found them, how would they prove that the installation was not tested, and not installed by competent persons. You could have tested it with fully calibrated equipment and just discarded the results. I'm not aware of any law requiring you to keep these records for non-notifiable work. Please correct me if I'm wrong!

When are you going to put your spade back in your shed?

 

[Darkwood]

This doesn't seem to be the case as I can see from other posts on the forum.

First people say I don't know what I'm doing, but fail to tell me how my installation isn't compliant. Next they say I need test equipment. When I tell them I've got it, they fall back on telling me I don't know how to use it. If I did know how to use it, what would be the point in coming on this forum in the first place? It does seem as though I can't win, and perhaps that explains my frustration?

We cannot tell you if your existing installation is or isn't compliant without inspecting and testing it ourselves, to assume it is can be dangerous so we are always better to tell you you need to confirm the existing circuit you intend to alter or add to is safe and this can only be done with experience, knowledge of the regulations and knowledge of using the test equipment and how to interpret the results...The regulations are clear on this fact so having a meter you cannot use or interpret means it is pointless having it and as I expressed above BS761, 610-5 says that to use the test equipment you need to be skilled to do so i.e. competent to use and interpret the results.
Reading can comply but may show issues that only a skilled person could spot and this may give concerns to do other checks so we cannot relay over the forum how to use the meter and interpret the results.

The work you are trying to undertake goes beyond basic DIY and should be done either by a competent professional or by yourself under the guidance of a competent professional and not from a step by step guide over a forum, this is not what this section is about, if you have test equipment and do not know how to use it or interpret the results it gives then you should not be using it.
Electricity kills and needs a very high level of respect, I admire your enthusiasm for wanting to try do all the work but we must limit the advice we can offer to a DIYer to ensure their safety and that of their property and family, this is why I am saying that the work you wish to undertake goes a little beyond what this section is about, we are not telling you not to do the work we are giving you the best advice here in that you should have your work overseen by a competent person and tested after by one.

Do you own a copy of the Yellow BS7671 (approx £80) which will have the tables listed to interpret the meter readings, your existing circuits and set-up will determine the exact column and values you need to be looking at and this varies from installation to installation, your earthing and bonding arrangements need to be confirmed for you incoming supply too... the list goes on and without you having the knowledge to recognise or interpret this you will not be able to provide us with the info' required to confirm that your existing installation is safe and the work you undertake will be safe.

Reading through your first post it is very clear your knowledge of electrics is poor and your suggestions are somewhat dangerous, hence albeit quite bluntly, you were told to get an Electrician in, and to be fair this is the best advice reading through your posts so please take it, trying to save a few quid at the chance you put both your property, yourself and/or your family at risk isn't worth the risk.

 

[siimon]

Hi siimon. You don't seem to be seeing the picture....

You are certainly right about that.

Are you going to fill in your own cert?

No, I assumed I don't need to. Can you please point me in the direction of some references if you believe otherwise?

thanks.