Mains electricity cables running under footings

[christopher c]

Hi guys, I stumbled across this forum hoping to find s one answers to an issue I have. I am digging the footingd for a porch we are having built (permission given all clear by council ) however whilst digging I've come across some mains electricity cables.

I have since checked the deeds to the house and it mentions these. it seems that a previous owner gave permission for them to be laid in the boundary of the property in the early 70's. Question is , can they me bridged or will they need to be moved? I'm guessing the latter.

I'm happy to post pics if needed. Any help would be greatly appreciated.

Thanks.

Chris.

 

[christopher c]

Have building control approved this as pet your picture? The mesh does not look like it's constructed correctly and the footings don't look deep enough?

Hi Murdoch, yes they have. The footings are 1 m deep by 60 cm wide. What do you mean about the mesh? Thanks, Chris Caswell .

P.s. regards the earlier question the cables run to a sub station down the road.

 

[Midwest]

P.s. regards the earlier question the cables run to a sub station down the road.

Bet you don't have problems with frost in you garden during the winter!

 

[christopher c]

Bet you don't have problems with frost in you garden during the winter!

Ha ha. Hmm. Now you mention it. ..

 

[Octopus]

Hi Murdoch, yes they have. The footings are 1 m deep by 60 cm wide. What do you mean about the mesh? Thanks, Chris Caswell .

P.s. regards the earlier question the cables run to a sub station down the road.

Mesh? Steel rods - they are just running along the top as far as I can see and the "bridge" is quite wide over the wood! What are you building?

 

[christopher c]

Mesh? Steel rods - they are just running along the top as far as I can see and the "bridge" is quite wide over the wood! What are you building?

Hi Murdoch have you checked out all the pics buddy? I have cut down a sheet of b785 mesh and laid it in the adjoining trenches and then laid another strip in the trench in question. The strip was the full length of the trench and 550 mm wide. That strip is cantilevered by the strips in the adjoining trench. I have also put another strip ON TOP of that two inches aboves so That concrete can flow around the sheets of mesh.

We are building a single story porch. the side where the problem trench is and where the cables are will a 1.2m x 1m window in the wall so it will not be just solid brickwork. Using lightweight blocks too. The building control specified a minimum of six inches of concrete over the area we are discussing if using high tensile mesh. I have done two layers of mesh and poured 9 inches of concrete to be on the safe side.

 

[PEG]

Hi guys, just thought Id check in to let you know how Ive been getting on with all this. I called out Southern Electric and they sent two old timers out. They were great and had a look at the pipes and confirmed that they were High Voltage. 2 x 11,000 volts and 1x 7000 Volt. They went on to explain that rerouting them would not be an option because of cost. (They thought it would cost £30,000+) With that in mind, they said that the best bet would be to bridge the pipes/cables but to make sure I do a really good job of it.

I consulted my local councils building control and made them aware of the cables and sought guidance from them about how they wanted it done in order for them to be happy and pass it off.

Soooo, I had to build a box round the cables. 3 inch cavity round the pipes. (Sides and top) The box was made with 18mm structural ply using 4 inch x 2 inch battens. Seriously sturdy although of course one day it will eventually rot away.

Once the box was made and the BCO was happy with the box I made, he went on to explain that he wanted sheets of structural steel mesh in the trenches. He also specified that he wanted B785 mesh which is high tensile steel and very strong. We got two layers of it in the long trench where the cables were predominantly. We also managed to get a total of 9 inches of concrete in to that section on top of the box. (He specified a minimum of 6 inches was needed if B785 mesh was used but I wanted to be safe so went overkill) The mesh was cantilevered by mesh in the adjoining trenches which will help to add extra support when the box does eventually rot away.

I have the builders arriving next week to start the job which is exciting. It has taken along time and has been quite stressful getting to this stage as Ive been doing the work thus far myself. Ill be happy to hand over at this stage and watch the building go up.

Ill get some pics up of the work I had to carry out in due course.

...Good job that fork of yours,only perforated the gas pipe...:cheesy:

I wouldn't mind betting that once you have that steel cage wrapped round those HV cables,you could pop a tail on each end,and power yer house for free!

Seriously,appreciate the update on your project,and hope it goes well......just don't expect an accurate reading on a ships compass,in that porch