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DIY electrical work in downstairs toilet?

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I am installing a new downstairs toilet (toilet and small basin) as I only have 1 toilet upstairs and am interested to see peoples views on if I need an electrician Part P certified or if I can do the electrical works myself.

 

The existing light and wall switch are already in the correct place so the only other wiring that needs doing is for the extractor fan.

 

I am just being ultra cautious in how I go about this project as I have just applied for Building Regs and don't want to upset them doing things I shouldn't be doing.

 

Cheers guys

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It's not a special location as in containing a bath or shower. Go for it. You might get an over zealous BC insist on a pull cord rather than a wall switch. The old wet hands switch thing. Ask him how it's different from some kitchens. 

 

I would say how are you going to be able to prove the work you have done is safe without the proper test kit?

 

If you do get a sparks in ask for a Minor Works Certificate. 

Edited by Onoff
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In general, you can DIY some minor works provided you are a competent person, which doesn't mean being a member of a Part P accreditation scheme, but does mean that you have the knowledge and experience to do work that is compliant with BS7671.  The main restrictions are that you cannot do any work in a kitchen, bathroom or shower room as a DIY'er, with only a few exceptions.

 

There's a check list below that may help, but remember that if you DIY any work you may be required to show that you were competent to do so if something goes wrong and you end up facing the wrong end of legal action.  I'd wholeheartedly agree with @Onoffs comment about test gear.  You do need to test a new outlet to make sure that it's OK, and that doesn't mean just plugging something in and checking it works.  You need to know that it's compliant with BS7671 and that means having test gear to test that the insulation resistance is OK, that the polarity of the connections is OK and that the impedance of the fault loop path is OK, and that isn't the sort of kit most DIY'ers will have access to.

 

Part P checklist.txt

 

 

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32 minutes ago, JSHarris said:

You need to know that it's compliant with BS7671 and that means having test gear to test that the insulation resistance is OK, that the polarity of the connections is OK and that the impedance of the fault loop path is OK, and that isn't the sort of kit most DIY'ers will have access to.

 

@JSHarris @Onoff @ProDave so other than a Megger, what is the view on a decent meter that can do the basics that isn't eye watering on price..?

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My downstairs cloakroom (toilet, basin, washing machine) has a wall switch fir the light and it was signed off by my electrician.

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13 minutes ago, PeterW said:

 

@JSHarris @Onoff @ProDave so other than a Megger, what is the view on a decent meter that can do the basics that isn't eye watering on price..?

You can get individual insulation / continuity, loop, and rcd testers pretty cheap on ebay.

 

For a one off DIY job I would not get too hung up about the lack of calibration certificate. It is unlikely they will be than inaccurate.

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I haven't got an MFT. 

 

Got a combo Megger IR & low resistance ohmmeter. Then a Megger combo RCD and earth loop impedance tester.

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Lad at work just bought a pair of Uni-T meters from the Far East that between them cover everything I'm sure. Around £300 the pair I think

 

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7 minutes ago, Onoff said:

Around £300 the pair I think

 

I'll source an electrician 🤣

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My knockabout multimeter / clampmeter is Iso-tech. Had it for years and RS still calibrate it!

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1 hour ago, PeterW said:

 

@JSHarris @Onoff @ProDave so other than a Megger, what is the view on a decent meter that can do the basics that isn't eye watering on price..?

 

eBay is your friend.  I bought a multitester from there for around £60 (second hand) when we started our build.  It's a bit clunky, but does every test you need.  Mine's an old Unitest Telaris 0100 Plus, and was in calibration when I bought it.  As @ProDave rightly says, calibration isn't essential, but my local place only charge £30 plus VAT to calibrate it.  If you want to check one out, then all you really need is an accurate low value resistor, as nine times out of ten the only thing that changes is the low value resistance measurement, and much of the time that's the leads rather than the machine.  Plugging and unplugging all the leads a few times often gets rid of any odd low resistance readings (works when testing sockets, too, as does flicking the switch a few times if the socket hasn't been used for a time).  I keep a couple of big 50 W (only just to make them easy to use) low value resistors in the bag with mine, a 0.01 Ohm one and a 0.05 Ohm one.  I can easily check if the lead null is still OK by just using one of those resistors.

 

As for tests, my crappy old machine will do low value resistance (to 0.01 Ohms), insulation resistance (at both 250 V and 500V), automatic tests of R L to CPC and R L to N, together with the calculated fault current, both at 4.5 A (for non-RCD testing; gives a more accurate result) and also at something like 15mA when testing circuits with RCDs (so they don't trip).  It also has a normal auto-ranging AC and DC voltage and current measurement facility, like a normal multimeter.  Mine came with the optional 13 A plug calibrated lead, which is very handy.  Makes checking Zs and correct polarity at every outlet a doddle, and something you can do in seconds, with no need to take the outlet off the wall (although if doing an inspection you need to take a significant sample of them off the wall to physically check them, anyway).

 

You often see older separate instruments on eBay, too.  As a minimum I'd want the capability to measure low resistance (better than 0.05 Ohms, as that's the max in the guidance in GN3 for bonding), the ability to do insulation testing at 250 V and 500 V (a Megger will do this OK) and the ability to do loop impedance testing. 

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8 minutes ago, JSHarris said:

 

eBay is your friend.  I bought a multitester from there for around £60 (second hand) when we started our build.  It's a bit clunky, but does every test your need.  Mine's an old Unitest Telaris 0100 Plus, and was in calibration when I bought it.  As @ProDave rightly says, calibration isn't essential, but my local place only charge £30 plus VAT to calibrate it.  If you want to check one out, then all you really need is an accurate low value resistor, as nine times out of ten the only thing that changes is the low value resistance measurement, and much of the time that's the leads rather than the machine.  Plugging and unplugging all the leads a few times often gets rid of any odd low resistance readings (works when testing sockets, too, as does flicking the switch a few times if the socket hasn't been used for a time).  I keep a few big 50 W (only just to make them easy to use) low value resistors in the bag with mine, a 0.01 Ohm one and a 0.05 Ohm one.  I can easily check if the lead null is still OK by just using one of those resistors.

 

As for tests, my crappy old machine will do low value resistance (to 0.01 Ohms), insulation resistance (at both 250 V and 500V), automatic tests of R L to CPC and R L to N, together with the calculated fault current, both at 4.5 A (for non-RCD testing; gives a more accurate result) and also at something like 15mA when testing circuits with RCDs (so they don't trip).  It also has a normal auto-ranging AC and DC voltage and current measurement facility, like a normal multimeter.  Mine came with the optional 13 A plug calibrated lead, which is very handy.  Makes checking Zs at every outlet a doddle, and something you can do in seconds, with no need to take the outlet off the wall (although if doing an inspection you need to take a significant sample of them off the wall to physically check them, anyway).

 

You often see older separate instruments on eBay, too.  As a minimum I'd want the capability to measure low resistance (better than 0.05 Ohms, as that's the max in the guidance in GN3 for bonding), the ability to do insulation testing at 250 V and 500 V (a Megger will do this OK) and the ability to do loop impedance testing. 

 

Thank you so much for taking the time to explain, I really do need to start learning this stuff as I have a lot more electrical work to do in the future. I have just borrowed a book from a friend called The Part P Doctor and apparently it explains a lot about testing in laymen terms which is fantastic for someone like me with severe ADHD and minor Aspergers.

 

🙂

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All the testing stuff is in City &Guilds 2391, and there are on-line tutorials and check exams you can do.  There are also a fair few YouTube channels that explain the basics, and, rather curiously, testing misunderstandings often seem to crop up on some of the electrician's forums (and these are people that have done the exams).

 

Part P is really a separate issue, as it's a building regulation, not an electrical installation or testing qualification.  Electrical installation inspection and testing isn't a Part P issue, as Part P only covers some aspects of electrical installation.  The only tie-up is that in order to show that a new electrical installation complies with Part P (where that's needed) you need to inspect and test the work done, which is where needing some test equipment and knowing how to use it are key.

 

If I was to guess at the most common problems, then I'd suggest that they are things like missing grommets on back boxes, CPCs ("earths") not properly sleeved, wires not secured properly, with no conductor visible and the screws done up tightly (loose terminal screws seems to be a pretty common problem), CPCs not connected to both the outlet and the back box (if it's metal) and reversed polarity (line and neutral the wrong way around) on socket outlets.  Most of the above are really just a matter of taking care and having the hand skills needed to do things properly, which anyone can pick up.

 

There are a host of other important aspects to consider, but your best bet for allowable DIY electrical work isn't to stress over what's allowable and best, or good, practice and what's not, but just ask on here and someone will know the answer.  I used to teach this stuff years ago, but I still find myself looking in one of the books from time to time because I've forgotten something (I did a couple of weeks ago; as I'd forgotten stuff and had to look it up in the OSG, the On-Site Guide, a handy reference version of the regs). 

 

 

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1 hour ago, joe90 said:

My downstairs cloakroom (toilet, basin, washing machine) has a wall switch fir the light and it was signed off by my electrician.

 

You can put a wall switch pretty much anywhere in the house except in the zones around the bath or shower or other special places like saunas. This includes in a bath or shower room outside the zones. No controversy at all for a cloakroom like that. There's no zone round the toilet or, contrary to some diagrams on the web, the basin.

 

The only catch I can see if BC or anybody wants to be stroppy about it is that equipment should be specified by the manufacturer to be appropriate for the location. Looking around at specs from various manufacturers I couldn't find any that explicitly say they're OK for bath/shower rooms.

Edited by Ed Davies
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On 19/09/2018 at 11:50, JSHarris said:

The main restrictions are that you cannot do any work in a kitchen, bathroom or shower room as a DIY'er, with only a few exceptions. 

 

The kitchen being a 'special location' is no longer the case - it was removed a few years ago. 

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