Garden Cable

[hanspuch]

Hello all, my first post on this forum but you may understand why once reading the problem I have.

I've been in touch with several builders regarding an outbuilding. Some have said that they will install the electrics for this outbuilding (but I'll add they are not registered electricians).

I have said no to these guys and have instead opted for a seperate builder and electrician.

Now the problem is that the builder has said that he is only available to come over on Thursday to start the work and it will be completed in approximately 1 week. I called the electrician who I have used before and so want to use again but his wife informed me that he will not be available for another 2 weeks as he is working away.

I initially wanted to place the cable supplying electricity to the outbuilding underground. But as the builder will have laid the foundations by maybe Friday, the cabling won't be done by then as the electrician will not be available for another 2 weeks as it stands.

Now to overcome this problem, I'm wondering if it may be best for me to just lay some cabling in the ground and through the foundations and not connect anything to either end of it. When the electrician comes over, he can then connect up as needed.

Now the distance from the consumer Unit to the outbuilding is approximately 30m. There will be 1 lighting circuit with 4 lights connected to it and 1 radial circuit with 8 -10 sockets connected to it.

What size cable should I use? Which type? And finally, how deep should this be in the ground? - Is armoured cable good enough? Can this be pierced with gardening tools such as a garden fork etc?

Please be assured that there is no way that I want to get involved with the electrics. All I want to do is to lay this 1 cable so that the electrician can come in and do his job in the way that I'd like it to be done.

Thanks all.

 

[wingcoax]

Your best bet is to lay a 3inch pipe at least 450mm deep between the end points and let your electrician run the cable through that. Then he can sign off at the end of the job. PS don't forget to lay a pull cord through.

 

[PrenticeBoyofDerry]

Have you thought of asking the builder to lay an open ended duct in the foundation of the garage, so the cable can then be pulled through.
If you trust the electrician you are employing, it would be worth having word with him regarding the requirements and the best plan to go ahead with it.
I assume they have seen the job?
Depending on what rating you want the radial circuit, would depend on the size cable.
20A radial would require at least 4.0mm SWA
32A radial would require at least 6.0mm SWA, I would stick a 10.0mm in though
The cable should be buried at least 500mm.

 

[ponyagent]

well if u really are using a spark why dont you ask him?
he is the one who will have to sign it off

 

[hanspuch]

Your best bet is to lay a 3inch pipe at least 450mm deep between the end points and let your electrician run the cable through that. Then he can sign off at the end of the job. PS don't forget to lay a pull cord through.

Thanks for this guys, why not put a pull cord through it?

I've tried getting in touch with the electrician, but cannot do so, his wife has said he is away, I'm guessing he's working away or maybe on holiday?

 

[ban-all-sheds]

don't forget to lay a pull cord through.

why not put a pull cord through it?

 

[ban-all-sheds]

Your best bet is to lay a 3inch pipe at least 450mm deep between the end points and let your electrician run the cable through that.

e.g.

http://www.drainageonline.co.uk/Ducting/Black-Twinwall-Duct-x-50m-coil.htm

Use the supplied drawcord to pull something heavier through.

Put in 2 ducts, so that 1 can be used for phone/data cables if ever needed.

Keep the bends nice gentle sweeps.

Take photos of the trench with something to show the depth before backfilling.

Have you thought about where/how the cables will exit the house and enter the outbuilding?

 

[hanspuch]

don't forget to lay a pull cord through.

why not put a pull cord through it?

Ahhhh.... miss read that as dont lay a pull cord.... !!!!

ban-all-sheds wrote:
Have you thought about where/how the cables will exit the house and enter the outbuilding?

I'm leaving it to the electrician to work out how the cable should exit the house although I'm guessing it can be taken from the side of the house (just to the side of where the CU is located on the inside of the house), which leads the cabling into the garage on the outside.

In the outbuilding, if I lay the cable or what sounds like a better idea a guttering pipe, it will go through the foundations and come up out of the floor on the inside of the outbuilding.

I spoke with the builder this morning about the whole thing too and he suggested that he can build me some small pillars at the sides of the garden at 2 meter intervals and at a height of about 2' with some of the left over bricks. Then the electrician can install some garden lights in these for me to make them look like a garden feature. These pillars can then also support a 40mm plastic pipe which can hold the cabling inside it too? Does this sound safe?

He also suggested that the electrician can then use cheaper cabling instead of the armoured type if I do it using the pillars? Does this sound feasible and safe? The last thing I want to do is to have pillars in the garden and no pipe installed in the foundations only to have the electrician turn round and say that the 'pillars' idea is a no go?

 

[bernardgreen]

These pillars can then also support a 40mm plastic pipe which can hold the cabling inside it too? Does this sound safe? ~~~

He also suggested that the electrician can then use cheaper cabling instead of the armoured type if I do it using the pillars? Does this sound feasible and safe?

It is NOT safe, What happens when some one sits on that pipe suspended between the pillars, it collapses and the live cable is torn out of the terminals or it snaps under the person.

If the builder applies that lack of thought to the rest of the work you may have chosen the wrong builder.

The last thing I want to do is to have pillars in the garden and no pipe installed in the foundations only to have the electrician turn round and say that the 'pillars' idea is a no go?

If you have the pillars and wan't to have light on them then the builder will have to bring ducts up inside the pillar as he builds them or get the electrician to install the correct cable at the correct depth to each of the pillars. Digging the necesary trench next to the pillar after it is built could affect the stability of its foundation.

 

[ban-all-sheds]

I'm leaving it to the electrician to work out how the cable should exit the house although I'm guessing it can be taken from the side of the house (just to the side of where the CU is located on the inside of the house), which leads the cabling into the garage on the outside.

So where would the ducting come out of the ground?

What would happen to it when it comes out?

How will you seal the end so it doesn't fill with mud, water, leaves, animals?

In the outbuilding, if I lay the cable or what sounds like a better idea a guttering pipe,

Guttering pipe???

The last thing I want to do is to have pillars in the garden and no pipe installed in the foundations only to have the electrician turn round and say that the 'pillars' idea is a no go?

And the other last thing you want is anything going wrong with your project because you and your builder are trying to second guess the electrician.

Now the problem is that the builder has said that he is only available to come over on Thursday to start the work and it will be completed in approximately 1 week. I called the electrician who I have used before and so want to use again but his wife informed me that he will not be available for another 2 weeks as he is working away.

I'm starting to think that you need to do some decent project management here.

You'll have to put things on hold until you can get the necessary people involved at the right time, so that they can liaise with each other as required. You're paying professionals to do building and infrastructure work for you - I don't think you should put that investment at risk via amateurish project management.

 

[hanspuch]

These pillars can then also support a 40mm plastic pipe which can hold the cabling inside it too? Does this sound safe? ~~~

He also suggested that the electrician can then use cheaper cabling instead of the armoured type if I do it using the pillars? Does this sound feasible and safe?

It is NOT safe, What happens when some one sits on that pipe suspended between the pillars, it collapses and the live cable is torn out of the terminals or it snaps under the person.

If the builder applies that lack of thought to the rest of the work you may have chosen the wrong builder.

The last thing I want to do is to have pillars in the garden and no pipe installed in the foundations only to have the electrician turn round and say that the 'pillars' idea is a no go?

If you have the pillars and wan't to have light on them then the builder will have to bring ducts up inside the pillar as he builds them or get the electrician to install the correct cable at the correct depth to each of the pillars. Digging the necesary trench next to the pillar after it is built could affect the stability of its foundation.

He's a very good builder, but as I said earlier, not an electrician. Thanks for the ideas and help everyone. I've spoken to the builder and advised that I want the guttering pipe installed within the foundations to hold the cables.

 

[hanspuch]

I'm leaving it to the electrician to work out how the cable should exit the house although I'm guessing it can be taken from the side of the house (just to the side of where the CU is located on the inside of the house), which leads the cabling into the garage on the outside.

So where would the ducting come out of the ground?

What would happen to it when it comes out?

How will you seal the end so it doesn't fill with mud, water, leaves, animals?

In the outbuilding, if I lay the cable or what sounds like a better idea a guttering pipe,

Guttering pipe???

The last thing I want to do is to have pillars in the garden and no pipe installed in the foundations only to have the electrician turn round and say that the 'pillars' idea is a no go?

And the other last thing you want is anything going wrong with your project because you and your builder are trying to second guess the electrician.

Now the problem is that the builder has said that he is only available to come over on Thursday to start the work and it will be completed in approximately 1 week. I called the electrician who I have used before and so want to use again but his wife informed me that he will not be available for another 2 weeks as he is working away.

I'm starting to think that you need to do some decent project management here.

You'll have to put things on hold until you can get the necessary people involved at the right time, so that they can liaise with each other as required. You're paying professionals to do building and infrastructure work for you - I don't think you should put that investment at risk via amateurish project management.

^^^^

The ducting would come out of the ground within the outbuilding at one end and within the garage at the other end???? I'm hoping not to get mud, water, leaves or animals in either of those places lol ???? The ends will be closed off using end fittings with holes in them finished off with the electrical fitting rubber glands between the cables and the plastic fittings.

When I spoke to the builder, he advised that to be on the safe side, it'd be better to use a duct such as a WC waste pipe. This he explained is much stronger that the flexible types and can withstand more pressure from the mud above it as those tend to cave in over a period of time. I called it guttering - meant WC waste pipe.

Not really second guessing, more trying to future proof the building and trying to make sure we don't have to revisit it if possible. Partly the reason for asking for ideas on this forum. As neither me nor the builder are electricians, I thought it best to ask for advise from professional electricians to see if they could give me better advise.

I'm sorry my friend but you know nothing about me and I take offense to you judging me and telling me that my project management is not 'decent' enough. I'm pretty sure that as things go, nothing goes 100% to plan 100% of the time. There are always times when something does not go to plan and that's when the clever people try to find a solution rather than sit back and let things slide!

As previously mentioned, the builder only has this week to complete and then will be on another job for the next 3 months and the electrician is not available before then. I either wait a minumum of 3 months or I make an effort and try to do as best a job as possible.

Worst case scenario, after this the electrician needs to change something or the other and so be it, but at least I tried. Best case scenario, the electrician can come in and finish off his part of the work with no problem - means that what I did was the right thing to have done.....! The only alternative being that i sit on my backside and guarantee that the electrician HAS to do some sort of extra work which could have been avoided if I had not been so lazy as to sit there and do nothing at all!

 

[hanspuch]

I'm leaving it to the electrician to work out how the cable should exit the house although I'm guessing it can be taken from the side of the house (just to the side of where the CU is located on the inside of the house), which leads the cabling into the garage on the outside.

So where would the ducting come out of the ground?

What would happen to it when it comes out?

How will you seal the end so it doesn't fill with mud, water, leaves, animals?

In the outbuilding, if I lay the cable or what sounds like a better idea a guttering pipe,

Guttering pipe???

The last thing I want to do is to have pillars in the garden and no pipe installed in the foundations only to have the electrician turn round and say that the 'pillars' idea is a no go?

And the other last thing you want is anything going wrong with your project because you and your builder are trying to second guess the electrician.

Now the problem is that the builder has said that he is only available to come over on Thursday to start the work and it will be completed in approximately 1 week. I called the electrician who I have used before and so want to use again but his wife informed me that he will not be available for another 2 weeks as he is working away.

I'm starting to think that you need to do some decent project management here.

You'll have to put things on hold until you can get the necessary people involved at the right time, so that they can liaise with each other as required. You're paying professionals to do building and infrastructure work for you - I don't think you should put that investment at risk via amateurish project management.

^^^^

The ducting would come out of the ground within the outbuilding at one end and within the garage at the other end???? I'm hoping not to get mud, water, leaves or animals in either of those places lol ???? The ends will be closed off using end fittings with holes in them finished off with the electrical fitting rubber glands between the cables and the plastic fittings.

When I spoke to the builder, he advised that to be on the safe side, it'd be better to use a duct such as a WC waste pipe. This he explained is much stronger that the flexible types and can withstand more pressure from the mud above it as those tend to cave in over a period of time. I called it guttering - meant WC waste pipe.

Not really second guessing, more trying to future proof the building and trying to make sure we don't have to revisit it if possible. Partly the reason for asking for ideas on this forum. As neither me nor the builder are electricians, I thought it best to ask for advise from professional electricians to see if they could give me better advise.

I'm sorry my friend but you know nothing about me and I take offense to you judging me and telling me that my project management is not 'decent' enough. I'm pretty sure that as things go, nothing goes 100% to plan 100% of the time. There are always times when something does not go to plan and that's when the clever people try to find a solution rather than sit back and let things slide!

As previously mentioned, the builder only has this week to complete and then will be on another job for the next 3 months and the electrician is not available before then. I either wait a minumum of 3 months or I make an effort and try to do as best a job as possible.

Worst case scenario, after this the electrician needs to change something or the other and so be it, but at least I tried. Best case scenario, the electrician can come in and finish off his part of the work with no problem - means that what I did was the right thing to have done.....! The only alternative being that i sit on my backside and guarantee that the electrician HAS to do some sort of extra work which could have been avoided if I had not been so lazy as to sit there and do nothing at all!

 

[ban-all-sheds]

When I spoke to the builder, he advised that to be on the safe side, it'd be better to use a duct such as a WC waste pipe. This he explained is much stronger that the flexible types and can withstand more pressure from the mud above it as those tend to cave in over a period of time.

Check with the makers of twinwall ducting which is made with the intention that it be buried. I'd be surprised if that was prone to collapse.