Garage electrics - running cable through garden

[Rob Fox]

Hi,

I have asked an electrician to install electrics in my house's garage. I'm happy with the electrical work he has proposed and quoted for, but I wanted to check his approach to running the cable to the garage.

A armoured cable will exit the house through the meter cupboard on a side wall, run down the side of the house, and then across the garden to the garage. Most of the trench will be fairly easy to dig - the problem is that there is a brick path running along the side of the house. My electrician recommends taking up the brick path and its concrete base, digging the trench, and then re-laying the path afterwards.

Is this how all electricians would approach it, or would some electricians have the equipment to tunnel under a narrow (1 metre) path?

 

[telectrix]

agree with your electrician. easiest way is as he suggests. tunneling using a mole is not only expensive, but hit and miss. you could end up supplying you neighbour's chicken farm.

 

[Wilko]

A bit of spade and jackhammer work for a 1m garden path is what I'd be doing. If you internet search on directional drilling and you'll get a flavour of what's involved to bore it.

 

[telectrix]

dig it,plant it.fill it. stamp it .job done.

 

[Octopus]

If the cable is under slabs, then out doesn't need to be deep imho

 

[dinger809]

I think he is giving you the cheapest and simplest option. It is definitely how I would do it

 

[The Ghost]

@Rob Fox I am the electrician doing the work for you. Whats the idea of checking me out on this forum? Don't you trust me???

Joke!

 

[MJPD29]

If this is true it gave me a good laugh, caught out

 

[PEG]

Personally,i would dig two 1m square holes,each side of the path,concrete in two 3.5m poles,and run the cable across a heavy-duty 1m suspension cable.

I would do this work,while the customer was out...

 

[ipf]

Personally,i would dig two 1m square holes,each side of the path,concrete in two 3.5m poles,and run the cable across a heavy-duty 1m suspension cable.

I would do this work,while the customer was out...

........with 3 core flex.

 

[PEG]

........with 3 core flex.

Of course,and let us not forget,as per 18th,the derating factor,applying the mass of a wet blackbird,every 200mm,(it's four),and the middle two are lower...

 

[ipf]

Of course,and let us not forget,as per 18th,the derating factor,applying the mass of a wet blackbird,every 200mm,(it's four),and the middle two are lower...

....or an old pair of trainers, thrown over...

 

[Dave OCD]

I'm sure you could did a small hole either side of the paving slab and beat your way through underneath.

 

[PEG]

I'm sure you could did a small hole either side of the paving slab and beat your way through underneath.

Pure "Allo Allo"...and i love it

 

[Des 56]

Just make sure your aim is good

 

[I2C]

Regarding the regulations, an outdoor SWA (Steel-Wire-Armoured Cable) doesn't have specific advice, other than when burying it, it must be at a reasonable depth given it's location/path/route, with regards to the potential activities which may disturb/damage it.

It seems reasonable to bury the cable under the path to ensure it's kept safe and is unlikely to be damaged by gardening, however I understand the cost and inconvinence of this method and there are other possibilities.

If it's clear to run the cable under the lawn or flower-beds, this is entirely possible, however it would need to be buried significantly deeper to make sure it's not disturbed/damaged by gardening, which can also incur a higher price.

Conclusion:
The depth & location that the cable is buried at is mostly down to the electricians discretion. Burying the cable under the path is probably the safest option, but with reason, I'm sure they'd be happy to look at other possibilities.

 

[DPG]

Don't forget to bore another hole above it for the warning tape

 

[PEG]

Just make sure your aim is good

Just a comedy,only fools n horses story,but a mate of mine,used an auger,to put in some anchors,for a swinging chair...

He picked up the flexible cable,in a plastic conduit,for his electric gates,which went to a plug-top,in the front room...

It wound ALL the cable round the end of the bit,leaving the severed plug-top,still stuck in the extension socket,at the edge of his floor boards - but not before it dragged the tele,sat-box,dvd,glass table and all the ornaments,to a pile,in the corner

 

[Octopus]

Regarding the regulations, an outdoor SWA (Steel-Wire-Armoured Cable) doesn't have specific advice, other than when burying it, it must be at a reasonable depth given it's location/path/route, with regards to the potential activities which may disturb/damage it..

Which is yet another glaring omission from said regs. All they need to do is add a table of "guidance" then that would help immensely.

 

[DPG]

Always amazes me how prescriptive the regs are on some trivial items, but are vague on things like this.

 

[Squid]

@Rob Fox I am the electrician doing the work for you. Whats the idea of checking me out on this forum? Don't you trust me???

Joke!

Price just increased by 50%........

Not a Joke lol

 

[Dave OCD]

Jokes eh..... Well the woman who was admitted to A&E last night with a vacuum cleaner pipe stuck in her ##### is picking up nicely now.

 

[I2C]

Which is yet another glaring omission from said regs. All they need to do is add a table of "guidance" then that would help immensely.

I completely agree. While some parts of the regulations are overly-complicated, other parts are far to vague.

Examples:
- Buried SWA is a great example of vagueness
- Performing calculations in reference to several tables of information to size a piece of conduit/trunking based on the number of conductors used; with the sole reason being to prevent damage to insulation during installation (every other factor is considered during cable-calculations) is a great example of over-complicating things.

 

[Rob Fox]

Hi all,

Thanks for the replies. It's not that I didn't trust the electrician - I asked the question because I'm a bit of a geek and was hoping that there'd be a "clever" solution instead of the brute-force method of digging up and relaying the path.

I've gone ahead with the electrician's proposal, and he's arranged for a builder to dig up and relay the path. The job has been delayed due to bad weather, but they started work this morning.

 

[DPG]

Thanks for the feedback.