Ask a tradesman


External electric cables


I was working on a single storey roof today when I placed my angle grinder against the external chimney brickwork the grinder’s metal guard came into contact with two large cables which I had not noticed.

To my surprise my angle grinder casing exploded and the cables scorched. Upon further inspection the cables further up the gable end going towards the chimney are red and black (tut). The other end leads into the property - I presume to the consumer unit.

My question is this; who is responsible for the cost of the repairs (renewing the un-insulated wiring) - the homeowner or the supplier?


Going on from my original question, the wire runs down the chimney stack and is clipped against the render and is sheathed and this sheathing has been painted many times.

Where the wire runs down the slope of the single storey (along the lead abutment flashings) both wires have no sheathing to a length of approximately 1.5 - 2 lm. These exposed wires are weathered and look like thin SWR.

When the metal casing (not the blade) crossed both live and neutral there was an explosion and the burnt but still intact cable appears to be copper.

Would the lead flashing have contributed to the insulation of the wiring degrading over time to this property Circa 1954; as copper pipes do in

To make this clear the angle grinder was OFF and the blade stationary. The metal safety guard bridged the bare wires (live and neutral).

3 Answers from MyBuilder Electricians

If I'm understanding your description of the situation these cables should not have been uninsulated. The suppliers will have to repair the cables whatever but I cannot see they will be wanting to seek compensation from anyone for the surcumstances you have described. Just relieved nobody has been hurt.

I have read your description a few times and I am starting to think you mean without actually saying it that you cut into insulated incoming supply cables with an angle grinder by accident because you maybe did not see them. If the cables were not clearly visible I still believe the supply company will repair them with no come back to yourself but they should be repaired as CSA (the cable size) may have been seriously compromised by the angle grinder which could cause the cable to blow.

I take it you mean SWA and if the armour is live then this is extreemely dangerous and the supplier should be informed immediately.


Answered 4th Sep 2012

The repairs will need to be done by the Distribution Network Operator (DNO), the cost of the repairs will need to e covered by your insurance as you are liable for the damage. Probably around £750 - £1000 if a new service needs to be strung in from the nearest pole.


Answered 3rd Sep 2012

the supply cables up to and including the main fuse are the rsponsibility of the distributor, give them a call and think yourself lucky to be able to, regards Terry.


Answered 3rd Sep 2012

Post your job to find high quality tradesmen and get free quotes

Can’t find an answer? Ask a new question

Question Categories