Running sub main to garden

Joined
3 Oct 2007
Messages
31
Reaction score
0
Location
Oxfordshire
Country
United Kingdom
Got some questions on regs for running a sub main to a garden room.

I need to dig a trench for the sparkys to run a 10mm armoured cable from the existing board down to a garden room I am building. its a run of about 50m.

Can the cable be surface mounted? if so does it need any further protection?

Can it be both surface mounted and run underground?

How deep does it have to be?
As I understand it is at least 450mm, blinded to 150mm, black and yellow tape and shingled. Is that necessary for a garden? Or is that just what SSE do before the meter?

There is a trench dug for the sewage waste can I enlarge this and run alongside?

There is also water (750mm-1250mm deep unless insulated) and possibly data to get down to the garden room aswell.

I have been asked to put services 300mm apart before so would normally do this but as there will be waste, electric, water and possibly data is that necessary for all of those to be 300 apart? Could be a 900mm wide trench.

Thanks in advance
 
Sponsored Links
You should ask the electrician who you will no doubt be expecting to sign a certificate to say that he did the design.
 
Sponsored Links
Also, have you or your agent applied for Building Regulations approval yet? If so, what did you say, or allow to be said on your behalf, or by default allow your LABC to assume, would be the way that compliance with Part P would be achieved?

If you have yet to apply (sounds like you should get a move on ;) ), what will you say, etc?

You can't promise one thing then do another - they don't like that, and people have had completion certificates withheld as a result.
 
Sparkys were happy to run it surface or in the ground but the client wanted it buried.

BC wanted what I put in OP.

Minimum 450mm, blinded, cable in, more blinding then warning tape, shingle and then back filled
 
What's your role in all this? How come if there is a client it's not the electrician who is making electrical decisions?

And what did Building Control want/expect from the POV of certifications, both electrical and Building Regulations?
 
I have been asked to put services 300mm apart before so would normally do this but as there will be waste, electric, water and possibly data is that necessary for all of those to be 300 apart? Could be a 900mm wide trench.Thanks in advance
A few years ago faced with digging 50 metres of trench for a telephone cable I joking mentioned there was ample space in the duct in which the electricity supply was laid. I was told in writing by BT that if I could get the "armoured" phone cable through the duct then they would accept it. Not the simple UG cable but cable with a tough plastic duct about an inch in diameter. No problems with hum on the line.

I am led to believe the separation is primarily there for protection of un-ducted cables / pipes from workmen digging for another cable / pipe
 
BT use some grey armoured cables for adverse paths, just a shame they don't know how to gland them! They just foot the armour back over the sheath and wrap with tape!

I've seen this cable installed up through surface water drainage pipes in the past!
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top