how deep do you need to bury cables underground?

Question

I want to put an electrical supply to my garage. This would have to pass underneath my driveway. What is the minimum depth recommended to bury them at?

Answer 1

You'll want to make sure that the power supply line is about 2 feet under the ground, when you get to your drive way, the line will be fine right under the drive way, just be sure to replace the dirt that you removed from under the drive way to prevent the drive way from cracking under the stress of no support.

Answer 2

If you're running a power supply to a socket as well as lighting, be sure to use a 2.5mm Steel wire armoured cable with an RCD protection at the supply end.(ie your house).
Through garden soil, bury the cable a minimum of 8 inches onto a bed of sand. This depth avoids garden forks! If bending the cable, don't overdo the bending radius.
When you go underneath the driveway, thread the cable through a steel conduit. You'd be amazed how many people have to dig up their drive for the sake of a few quid when things go wrong, or the cable needs replacing at any time. It also helps to protect the drive from sinking later.Finally, dint be tempted to make any connections in the cable. One length from start to finish. It's also best to get a decent sparx to do it.
Happy wiring.

Answer 3

Electric has to be a minimum of 28" and before you dig call the Miss utility hotline. They will come out and locate all of the other underground utilities so that you don't end up dead or paying a fortune, and it's free. Plus in many states it is now the law.
Depending on where you live you may cut into phone line, fibre optic, electric, gas, cable, sewer, or water, and they are all expensive to repair. Just search / miss utility / for your state

Answer 4

check with your local building official general rule of thumb is 3' deep it must have at least 1' of clean sand on top of it and on top of the sand it must have "caution buried cable" this is a red caution tape with black letterig this and the sand are tell tale signs to anyone digging there in the future that there is electricity there , electricity is nothing to mess with and this needs to be done properly remember even if you as a homeowner wants to excavate anything even if with a shovel you should contact "dig safe" or "call before you dig" depending on what it is called in your area and by the way this is the law if you don't call and try to dig yourself and you break an underground cable you will be charged for the repair if you are still alive

Answer 5

Hi because you need to ask this I gather you are not an electrician so get one reason is since Jan this year you can't do any electric work out side in the garage, kitchen or bathroom as an electrician has to give a certificate to prove it's been done properly. You could how ever ask one do your self and then get them to check this will if done correctly save money to you.

Answer 6

0.5 meter minimum in soil liable to be dug over or otherwise cultivated. Use plastic warning tape at appx. half depth. Cable should be SWA with RCD protection at supply. Cable can be at shallower depth below a slabbed pathway or other hard area not liable to disturbance. Back fill around cable with sand, or soil free of stones, they can cause damage over time!

Answer 7

Ask your electrictian - you need one as it's notifiable

http://www.niceic.org.uk/downloads/Pocket%20Guide%208.pdf

but, to answer your question, 600mm (2ft) should do it.

http://www.rhs.org.uk/advice/profiles0903/safe_electricity.asp


also get some 'Buried Cable' marker tape to place above it in the trench, just to warn others when they are digging.

the regs say: "buried cables shall be marked by cable covers or a suitable marking tape. ... buried cables ... shall be at sufficient depth to avoid being damaged by any reasonable foreseeable disturbance of the ground"

IEE Guidance Note One states "A depth of burial less than 500mm is usually inadvisable as shallow laid cables may be inadvertently damaged"

A RCD and SWA (Steel Wired Armoured) cable is also a must, and these people (& B&Q etc) sell it http://www.water-garden.co.uk/Power_Management.php

Answer 8

LOL in the highlands of Scotland you just leave the cable on the side of the road if telephone - and then wehn locals complain, you tell them it is a special "self burying cable".

This means "the cable will eventually get covered over by moss, lichen and leaves"

Mark

Answer 9

No minimum depth as such but you must use an armoured cable if it is not in conduit. An rcd at the supply end is a good idea.

Answer 10

Depending on where you live you may have to call Dig Safe first before you lay any cables down. I just went through dig safe training yesterday and I was told 18".