Cable buried in a flower bed

[Pretty Mouth]

Had a look at a job a few days ago where, should the work go ahead, it would be necessary to run a cable under a flower bed. This is the only option acceptable to the customer unfortunately. The cable will be low voltage, ELV is not an option as the cable will supply power to sockets.

The flower bed is raised by about a foot, is narrow, and lies between a path and a fence. I suspect the concrete holding the fence posts will prevent me burying the cable to a decent depth.

Has anyone got any clever ways of protecting such a cable from damage when the flower beds get dug over?

 

[littlespark]

Can you get it deep enough to avoid any general digging over?

If it’s armoured, it shouldn’t get damaged… also slide some white pvc conduit over it as well as additional protection… and easier to see.

What about clipping on surface behind the bed? Fence or wall?

 

[Dustydazzler]

As above I would use SWA and run this through some white conduit where it passes under the soil in the flowed bed, perhaps even some yellow warning tape over the top

 

[brianmoooore]

Concrete slabs over the top would do the job. Even 4" concrete blocks on their sides at a push.

 

[catdog1121]

Have a look at cable protection tiles, or cable warning tiles, if anyone digs they will hit that and will protect the cable..

 

[Pretty Mouth]

Thanks for the comments guys, it's a great help.

The customer doesn't want the cable clipped to the fence unfortunately. She is quite particular about minimising visible cables. I'll not know until I start digging, but looking at it, I'm not at all confident I'll be able to get deep enough to avoid contact from spades when digging.

On a similar job I was able to run the cable in conduit, then bed a course of bricks of bricks on top. It worked well because there was brickwork immediately below the conduit too (it was a brick built raised bed), so was totally solid. I'm not sure that would work as well in this instance, as much of the run will probably be soil beneath. Perhaps that doesn't matter though.

 

[Pretty Mouth]

Have a look at cable protection tiles, or cable warning tiles, if anyone digs they will hit that and will protect the cable..

This sort of thing?

Jointing Tech: The UKs leading distributor of specialis

Jointing Tech are the leading distributor of specialist power cable and accessories, supplying products and services that develop, connect and maintain the UK’s electrical infrastructure

www.jointingtech.co.uk

 

[brianmoooore]

This sort of thing?

Jointing Tech: The UKs leading distributor of specialis

Jointing Tech are the leading distributor of specialist power cable and accessories, supplying products and services that develop, connect and maintain the UK’s electrical infrastructure

www.jointingtech.co.uk

Might work against someone digging with a shovel or spade, but not so well against someone stabbing away with a fork.

 

[littlespark]

Run it in non armoured, close to surface…. They’ll only stab it with a fork the once!

 

[OnlQQker]

You could get scaffold tube which is 45mm + internal diameter 2 Metre Aluminium Tube - Alloy Scaffolding Tube - https://www.scaffolding-direct.co.uk/alloy-scaffolding-tube-48mm-tube-clamp-key-clamp-tube-or-scaffolding-4.aspx

And then line it on the inside with plastic 32mm pipe FloPlast Solvent Weld Waste Pipe White 32mm x 3m - https://www.NoLinkingToThis/p/floplast-solvent-weld-waste-pipe-white-32mm-x-3m/61967

If you need to make it really long you could join the tubes together with one of these Pressed Sleeve Coupler Scaffolding Fittings - https://www.scaffolding-direct.co.uk/scaffold-clamp-pressed-steel-sleeve-coupler-25-.aspx

For 32 mm pipe connector FloPlast Straight Couplers 32 x 32mm White 5 Pack - https://www.NoLinkingToThis/p/floplast-straight-couplers-32-x-32mm-white-5-pack/38660

 

[timhoward]

A lot comes down to budget. There were once cable protection/marker bricks (?Baldwin) available that were perfect for this kind of thing but they don't seem to be as commonly available now, and the ones that turn up on line look expensive.
(And as I found out once, they aren't plumber proof when someone hands over the keys to a mini-digger...)

I'm assuming that galv conduit is too much of a faff to consider? Most manufacturers state it requires no extra anti-corrosion protection when in soil or concrete.
On that basis is galv trunking too expensive and over the top?

 

[pirate]

Maybe consider SWA threaded through MDPE water pipe which is pretty tough and won't rust

 

[littlespark]

Maybe consider SWA threaded through MDPE water pipe which is pretty tough and won't rust

And wait for the next (non)plumber handyman to come along thinking it would be a handy pipe to cut into for a garden tap.

 

[Pretty Mouth]

A lot comes down to budget. There were once cable protection/marker bricks (?Baldwin) available that were perfect for this kind of thing but they don't seem to be as commonly available now, and the ones that turn up on line look expensive.
(And as I found out once, they aren't plumber proof when someone hands over the keys to a mini-digger...)

I'm assuming that galv conduit is too much of a faff to consider? Most manufacturers state it requires no extra anti-corrosion protection when in soil or concrete.
On that basis is galv trunking too expensive and over the top?

I'm surprised that manufacturers are suggesting galv conduit for direct burial in soil. I would've thought it would rust through eventually?

 

[Pretty Mouth]

Maybe consider SWA threaded through MDPE water pipe which is pretty tough and won't rust

I had considered this, perhaps using black pipe with electrical warning tape wrapped around it. Have seen this done a couple of times on farm instalations, and it seemed to work well, it is very tough. Kinda breaks a reg or 2 though doesn't it?

 

[nicebutdim]

I had considered this, perhaps using black pipe with electrical warning tape wrapped around it. Have seen this done a couple of times on farm instalations, and it seemed to work well, it is very tough. Kinda breaks a reg or 2 though doesn't it?

How about flexible ducting wrapped with tape? Still fairly tough and no regs contravened.

 

[Dustydazzler]

Just saw this on the news

Man electrocuted after drilling through mains cable under garden

A Swindon man was airlifted to hospital after drilling through a mains electricity cable while carrying out DIY in his front garden.

uk.yahoo.com

 

[pc1966]

I'm surprised that manufacturers are suggesting galv conduit for direct burial in soil. I would've thought it would rust through eventually?

I would expect so. You can get stainless but at a price:

20mm Stainless Steel Conduit 3mts - 304 Grade

Based in Northern Ireland, Dungannon Electrical Wholesale is a family run business providing electrical goods and equipment to both Trades and the Public.

www.dungannonelectrical.co.uk

 

[swaRRR]

My first thought was plastic conduit but obv a spade can break through this. Then i thought that cheap ali pipe you can get from DIY shops but then it'd need earthing.

Personally i'd just run it in a piece of metal conduit with a through-box for access and fly lead it on the inside for the earth.

 

[swaRRR]

Just saw this on the news

Man electrocuted after drilling through mains cable under garden

A Swindon man was airlifted to hospital after drilling through a mains electricity cable while carrying out DIY in his front garden.

uk.yahoo.com

Isn't electrocution where it kills you?