Getting power to a shed

TBR said:
I found a recommended electrician, but unfortunately he doesn't do any certificates. He's semi retired and used to be registered but its no longer worth him paying his membership because of the amount of work he does now. Is the certificate important?
With building departments computerizing and power companies monitoring power consumption your chances of the work being found to be without a certificate are becoming more likely. You might not have a problem until you sell and the building inspector or buyer's house inspector find you did not get the certificate. You will then need to pay for a licensed electrician to inspect and possibly upgrade the work.

You might want to discuss this with your friend and see if he can do the work and if he has a friend that will get the required permit and inspect the work. You might not save that much.
 
If you were to sell the house, disconnect the wiring if it's not certified. Nowt anyone can complain about then!

There is no way on earth a power company can tell from the power consumption the condition of the installation, be it certified or not...
 
richy3333 said:
Someone mentioned BS7671:2008 which are the Wiring Regulations. The current Standard is BS7671:2011 (and they're possibly going to be updated again next year).

And they we're right.

It's BS7671:2008(2011) (the green one)

Where the (2011) refers to amendment 1 or Amd1:2011

Perhaps that's what you were thinking of?

Although we're now on Amd2 and soon to be Amd3:2015 - it's not terribly relevant unless you want to charge your g-wiz at home or in the shed! :)

L
 
E30Mark said:
If you were to sell the house, disconnect the wiring if it's not certified. Nowt anyone can complain about then!

There is no way on earth a power company can tell from the power consumption the condition of the installation, be it certified or not...

But I'm guessing that a not having a certificate might invalidate any insurance if anything should go wrong with the wiring.
 
CrazyLarry said:
richy3333 said:
Someone mentioned BS7671:2008 which are the Wiring Regulations. The current Standard is BS7671:2011 (and they're possibly going to be updated again next year).

And they we're right.

It's BS7671:2008(2011) (the green one)

Where the (2011) refers to amendment 1 or Amd1:2011

Perhaps that's what you were thinking of?

Although we're now on Amd2 and soon to be Amd3:2015 - it's not terribly relevant unless you want to charge your g-wiz at home or in the shed! :)

L

Not really BS7671:2008 (using your definitions) is the red book and as you say after the subsequent amendments we are now on the green book. The amendments relate to more than charging electric cars.
 
TBR said:
I found a recommended electrician, but unfortunately he doesn't do any certificates. He's semi retired and used to be registered but its no longer worth him paying his membership because of the amount of work he does now. Is the certificate important?

This is where the electrical industry is a nightmare. You don't have to be registered with a scheme to 'do' certificates. End of. You have to be competent to undertake electrical work. The inspection and testing once the work has been done allows the electrician to complete an Electrical Installation Certificate and prove the work is safe. Any proper spark should know that. If he doesn't have test equipment then he can't prove his work is safe. If he won't give you a certificate then that raises a number of considerations. Is this because he wants the ability to deny he ever did the work in the event it goes wrong - paper trail? Is he insured? PL and professional indemnity (he has to design the circuit(s)).

You also still need to check about LABC certification/approval. This is where scheme registration is applicable. If you need to notify to LABC and he is scheme registered he can do this for you. If he is not then you will have to contact the LABC yourself to get the work checked and signed off. Usually costs a few hundred pounds.
 
TBR said:
E30Mark said:
If you were to sell the house, disconnect the wiring if it's not certified. Nowt anyone can complain about then!

There is no way on earth a power company can tell from the power consumption the condition of the installation, be it certified or not...

But I'm guessing that a not having a certificate might invalidate any insurance if anything should go wrong with the wiring.

Quite possibly, insurers will squirm out where they can.

We deducted £10K off our house purchase because the previous owner did his own wiring and couldn't prove it was safe. As it was some aspects were imminently dangerous!
 
richy3333 said:
Quite possibly, insurers will squirm out where they can.

We deducted £10K off our house purchase because the previous owner did his own wiring and couldn't prove it was safe. As it was some aspects were imminently dangerous!

But I will bet it didn't cost you 10k to correct! Nice negotiating  [big grin]
 
Try the IET  http://electrical.theiet.org/wiring-regulations/
Hence BS7671:2008(2011)

SWA is the way to go, you have a spare way on a 17th ed CU, like Jonny round boy says pop the manhole cover to check the easiest path for an underground run and then decide how much will be underground v along the wall. If you're going to do the digging yourself. As stated 500mm is the minimum but there's a lot less fuss if you can bury a large pipe as a run. Direct burying SWA will involve sand above and below to prevent damage to the sheath from stones etc. Either way put warning tape about 300mm down for the entire length and take a photograph of the route for future reference.

Do have a small DB / CU placed in the shed, Schneider / MK / Hagar there are plenty of good brands. IMHO the quality of the brand / ease of installation matters most, personally I favour TLC as a supplier (service with a smile) but even Toolstation can supply a functional plastic conduit box!

A small CU with it's own RCD and 2 to 4 ways gives you one MCB for a socket or two another for lighting as well as 2 spares ways for the future.

As others have mentioned make sure your earthing is checked, with properly installed SWA there's a good likelyhood you'll be able to rely on the existing earth provision but make sure.

Do have someone who can legally issue you a cert and do make sure it's someone who actually tests what they say they do. Which applies regardless of what scheme or quals they have! This means they will have to do the cable installation / test / commisioning to sign for it. But you can still do much of the planning and preparation esp groundworks. Do overestimate your future needs a bit and build it in.

With your catV! run a separate plastic conduit make sure it's glue jointed to seal it and use gaskets / glands at covers / ends and either run 2 or 3 lengths straight away or make sure you can pull through if you need to, terminate both ends at shielded sockets and pay great care not to compromise the sheilding. One tip is to use grommets for entry holes even if the back box is plastic.

One last question: how far will you have to walk from your armchair to fill the kettle?

EDIT>  personal attack towards other forum member removed.

 
Not sure what the rules are over there, but in the U.S. your Cat5e would have to be underground rated even if it is contained in PVC / plastic pipe. It's probably a good idea even if it isn't required. The cost isn't that much more, BUT it can be a huge PITA to find it.

Underground rated Cat5e or Cat6 is easily identified over here as it has a bright orange sheath. Even a novice can identify it at a glance then.

Oh - the same is true of coax for the 'telly' (hey, I'm trying?!). It also need to be underground rated and it also has a bright orange sheath.

One other note about what we call low voltage (network) wire: Best practice dictates that it be around 12" (um...300mm) AWAY from your mains wires. This separation can be reduced a bit if it's surrounded by earth, and can be reduced even more if you use shielded network wire as suggested by CrazyLarry.

I offer my comments in hopes of helping you 'get it right the first time', based on my experience as a network guy who also wired his own home with multiple breaker panels (I think our equivalent of your CU's?) and was complimented by the electrical inspector at having 'done a better job than most of the licensed guys he sees'.

IMPORTANT - I want to be clear that do not know the regulations or code in the UK, so verify with the appropriate authority or contractor before you take anything I said as being valid for your situation, OK? I'm trying to help, and I'd feel terrible if something I suggested made it worse or harder for you...
 
wow said:
Not sure what the rules are over there, but in the U.S. your Cat5e would have to be underground rated even if it is contained in PVC / plastic pipe.

Oh - the same is true of coax for the 'telly' (hey, I'm trying?!). It also need to be underground rated and it also has a bright orange sheath.

IMPORTANT - I want to be clear that do not know the regulations or code in the UK,

In the UK, there are, as far as I'm aware, zero regulations when it comes to cat-5/6, co-ax, etc. You can pretty much do what you like with it!
 
I worked out of a site trailer with a 50 Amp hook-up that was tied to a RV style drop cord. The GC would provide the power outlet at the site. we were building schools ( 2 at once ) and were at the site for over a year. I have built Small houses (RV size)  that uses this same style hook-up. A hook-up like I am reading about in the other messages is the best way to go, get a sparky, have them do the brainy (read in stuff that can kill you) work and you do the bull work (stuff they don't want to do) and save a few pounds. The thing is if you need a temp set-up you might look at RV/ marine hook-ups. Brent
 
Section 528 of the UK Regs deals with the proximity of wiring systems to other services.
 
We usually run a few lengths of this in

http://www.pipes-underground.com/cable-ducting.html

, you'd probably be looking at the 32mm stuff one for the SWA or HiTuff the other for your catV, it's smooth bore so cables glide in, and it pretty much future proofs you for any additions. Me personally I'd put a metal clad DB in the shed and do everything in high impact pvc conduit with metal clad socket outlets, or if you wanted to really push the boat out galv conduit :). Cable sizing as mentioned above needs calculation, 4mm to 6mm would be a good starting point.

 
I just started ringing around electricians yesterday. 1 chap said that it would take  one day and he would charge  £180 plus materials. Hopefully next week ill be able to get some of them to pay a visit so they can advise the best way to dig through the concrete or reroute around the house. I've ordered a catalogue from tlc so that when they are round we can build a shopping list.

i found on youtube interesting video about how to get a pull cord through a pipe using a vacuum cleaner and some polystyrene on a hook to act as a piston. Very useful tip !
 
Here are some more detailed photos...
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Finally, I got an electrician round last week and he's just quoted £1000 for the job. I asked for 2 security lights on the house, a light and 5 double sockets in the shed.

He looked at the concrete and i was worried that some of the underground pipes my crack, so we decided it would be best to run the armoured cable behind kitchen units, out through the back wall, under the doorstep and around the house to the other side of the garden and then down to the shed.

3 days labour at £240 per day. The rest is materials of which £140 for 50m of 6mm swa. £40 for a 2 way consumer unit.

Looking for ways to get this cost below £300.

Another recommended semi retired electrician quoted £30 an hour. But he couldn't do any certification work because he is no longer a member of necessary body. He used to be certified but nowadays he does less work and so is not worth it for him to pay his membership.
 
£240 a day seems cheap to me for London, but 3 days is excessive for all that work. I'd say 2 tops. If breaking the concrete out is part of that time can you not dig the trench to save a few pounds? Else can he not use a catinery wire to save burying the cable?

£140 for 50m of 6mm doesn't sound bad
 
richy3333 said:
£240 a day seems cheap to me for London, but 3 days is excessive for all that work. I'd say 2 tops. If breaking the concrete out is part of that time can you not dig the trench to save a few pounds? Else can he not use a catinery wire to save burying the cable?

£140 for 50m of 6mm doesn't sound bad
No digging for that quote. We aggreed it might crack a pipe underground
 
E30Mark said:
There are a few factors to be considered here!

All electrical installations should comply with BS7671:2008

What type of fuse-board do you already have in the house?... Does it have a spare way for another MCB? Do you have RCD protection on the existing fuse-board?

A 2kw load over 80' will produce a volt drop of around 6V with a 1.5mm2 SWA cable. Maximum cable load would be approx 16A

A 2.5mm2 SWA will have less volt drop and a max load of approx 21A

Without seeing the whole length of where you plan to run the cable it's hard to give a complete answer, but basically I'd run a 2.5mm2 SWA clipped to the house wall so you don't have to dig past the drains, and then bury it where necessary. The regs don't give an exact depth to bury the cable, but state it must be a 'suitable depth'.... rule of thumb is 18" down.

Your not allowed to clip to a fence, as it's not deemed a permanent structure, funnily enough, your allowed to leave the armoured cable laying on the surface un-buried...

An electrician has quoted for 6mm2 SWA. It's almost twice the price of 2.5mm2. £110 as opposed to £60. Just wondering if there is a good reason for this?
 
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