Outbuilding - connected via 13A plug - Building Regs part P?

Discussion in 'Electricians' Talk' started by mlawson, Dec 7, 2017.

  1. mlawson

    mlawson New Member

    Hi, I have a workshop in my garden which I constructed myself within which I use the occasional power tool. Inside I have a ring main serving a number of 13A sockets, I also have a separate lighting circuit for the lights. Both are connected via a RCCB inside a 2 circuit "shed" consumer unit. This then goes via SWA cable to the house. I fitted and wired all these myself in accordance to BS 7671:2008 +A1:2011. I am not a qualified electrician but consider myself to be reasonably competent and know my way around BS standards.

    The house has a 13A socket inside a weatherproof box and located in a very sheltered position.

    I have two questions and would appreciate some guidance from some experts in this field please:

    I know the "correct" way of finishing off the installation would be either to go direct to the consumer unit of the house and create a new circuit or to replace the socket on the side of the house with a fused spur and connect the SWA to that.... but...

    Q1. If I fit a 13A plug on the end of the SWA and plug it into the socket, does the workshop require any building regs notification and/or control? (in theory)

    Q2. If I abandoned the fixed wiring I had inside my workshop and simply ran some cheapo (but CE marked) long extension lead with lots of sockets on it, and plugged it into the 13A socket on the side of my house, does this require any building regs notification and/or control?

    And finally perhaps a provocative question, which would be safer?
  2. seneca

    seneca Screwfix Select

    You'll have fun trying to get swa into a 13amp plug top! One way would be to properly gland the swa into a metal adaptable box and then run a 1.5mm t/e flexible cable into the 13 a plug. This wouldn't be notifiable as it's just essentially an extension lead and not fixed wiring. Check whether you have rcd protection at the fuse board, if not use a plug in (Powerbreaker) type.
    mlawson likes this.
  3. Dr Bodgit

    Dr Bodgit Super Member

    You're very brave posting such a question on here :p

    Out of interest, what size SWA and length run is it?
    mlawson likes this.
  4. Coloumb

    Coloumb Screwfix Select

    If you connect that lot via a 13 amp plug then none of it will comply with 7671 since it's not part of the fixed wiring, even though technically it is "fixed". Anyway, it's doubtful you will ever be able to "get" your work to be to compliant with 7671 without an EIC anyway, for which you will need specialist testing equipment and some knowledge of testing and inspecting, in my day it's a C&G 2831 and 2391. And I can tell you from personal experience 2391 is not an easy exam.

    Having said that, you don't "need" a BC cert, the only problem you will have is you will be asked to provide one if/when you come to sell the property. This can be got round by the purchaser buying an indemnity but it puts the purchaser in a stronger bargaining position since it's may have to be ripped out and done again if the buyer wants a BC cert. The alternative is to lie about it but then your committing fraud.
    mlawson likes this.
  5. DIYDave.

    DIYDave. Screwfix Select

    How would you earth the sheath of the swa, assuming you could actually terminate with a 3 pin plug

    Don’t know if it actually has to be earthed for regs but seems to make sense to do so
    mlawson likes this.
  6. mlawson

    mlawson New Member

    Hi, (yes I know!) - it's 4mm SWA, about 6m length.
  7. mlawson

    mlawson New Member

    Hi, the sheath of SWA is there to provide strength, it does not have to be earthed. The 3 core cable on the inside does contain an earth. I also have a CAT6 network cable running outside, again the outer sheath isn't earthed (and doesn't need to be).

    It did take a while to wire up neatly.

    Attached Files:

  8. Coloumb

    Coloumb Screwfix Select

    That's dog rough mate. Totally not the way do terminate SWA. How can the steel be properly earthed? For support? That whole lot could be live under certain fault conditions. Dangerous imo.
  9. retiredsparks

    retiredsparks Super Member

    I think you will find that the SWA does need to be 'earthed' one way or another.
    Cat 6 does not carry 240 Vac......but what do you connect the drain wire to ?
    nigel willson likes this.
  10. mlawson

    mlawson New Member

    I would stress, this is temporary.

    Putting this aside, the question is - would anything downstream from the 13A plug require building regs?
  11. mlawson

    mlawson New Member

    Yes, you appear to be correct. When I come to wire the SWA more permanently I will connect the armour to earth.

    Cat 6 on the other hand is a SELV circuit without an earth being present to connect it to.
  12. Coloumb

    Coloumb Screwfix Select

    Ah, that's ok then. It makes it much safer.:rolleyes:
  13. retiredsparks

    retiredsparks Super Member

    Cat 6..is SELV?
    Really ?
  14. mlawson

    mlawson New Member

    Well it ain't TNV
  15. Coloumb

    Coloumb Screwfix Select

    I think your largely missing the point. Does it matter if it complies or not? It's makes no difference. The question you should be asking is; is this a sensible/suitable/safe way to run electric to my shed on a temporary basis? To which there can only be one answer.

    No it isn't.
  16. DIYDave.

    DIYDave. Screwfix Select

    It did take a while to wire up neatly.[/QUOTE]

    I must be viewing a different picture then :confused: !

    Same old / same old

    Sockets and light lights in shed work so that’s the paramount number 1 factor - flick the switch and hey presto - I’ve got lights ;)

    Crack on, you seem to have everything totally covered with this installation ......
    leesparkykent likes this.
  17. Dr Bodgit

    Dr Bodgit Super Member

    I rest my case!!
    mlawson likes this.
  18. Bob Rathbone

    Bob Rathbone Screwfix Select

    Your suggestion to run an extension lead to the shed and abandoning the fixed installation is not so silly as it might first appear, it is rough but provided you use CE marked leads and RCD protection ensuring that all plugs and sockets are protected from rain and water and the cable is safely routed, it does not need further certification. Strange isn't it that this can be done without contravening and rules. Seneca's suggestion will solve the issue of the SWA supply end but the installation in the shed remains an issue.
  19. Bazza-spark

    Bazza-spark Screwfix Select

    You haven't got a ring main, you may have a ring final circuit.

    It is not wired according to BS 7671, it is obvious you are not an electrician, and I question your competence seeing that photo. I also question your knowledge of this particular standard.

    It isn't weatherproof in that condition.

    It does have to be earthed as it provides the safe connection to earth to clear the circuit protective device in the event of somebody spearing the cable.

    My answer to your 3 questions is to get a qualified spark in to do it correctly and safely. There are issues you have not considered such as the earthing arrangement at the house end (TT, TNS, TNCS) that could lead to a dangerous situation.

    Also may be worth a trip to Specsavers (other opticians are available!)

    Kind regards
    leesparkykent and DIYDave. like this.
  20. nigel willson

    nigel willson Screwfix Select

    Of course you do! It’s a Protective Conductor!!!

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