Tayross Associates Ltd

CIOB Chartered Building Consultants



Managing Director: Carl O'Boyle (RICS Membership No: 5628079)



Professionalism & Integrity
In Construction


Membership No: 1486929

High/Low Voltage Cable Discovered During a RICS Level 3 Building Survey

Manhole in garden build over agreement

We were recently instructed by our Client to carry out an RICS Level 3 Building Survey on a detached house in Pinner. And as part of our Building Surveys we always ask clients to let us know if they have any plans for the property so that we can advise them on the best way forward.

On this particular occasion, the Client wanted us to advise on the feasibility of a side and rear extension to expand the footprint of the property. However, the desktop study revealed that there was a high voltage cable running diagonally across the site just where the client wanted to build their extension.

Taking this into consideration, we advised that it would not be possible to build a side extension with this sort of cable underground. We also advised that the cable most likely could be re-routed for a sum of between £10,000 and £20,000 but it would have to be done using a contractor approved by the utility company or by the utility company themselves.

Underground Electrical Cable in Garden

Although this is an expensive operation, it can be done and would allow our Client to build on the side of the property and also to renegotiate the sale price.

During our site visit we also advised that there was a shared drain at the rear of the property where the Client also wished to extend. We advised that as this part of the pipework was actually at the beginning of the run, there should be no need for a Build Over Agreement as this section of pipework did not take the drainage of the other neighbours’.

Going forward, we have advised the Client to meet with the utility company on site to discuss the re-routing of the cabling underground and the Client is also contacting the utility company to confirm that the drainage at the rear of the property does not form part of the public sewer, and therefore they can be built without a Build Over Agreement which can be time-consuming and very costly.

This article was written by Carl O’Boyle BSc MRICS FCIOB MFPWS. Carl is a full professional member of the Royal Institution of Chartered Surveyors, a member of the Faculty of Party Wall Surveyors and a Fellow of the Chartered Institute of Building for which he currently sits on the CIOB professional conduct committee and adjudications panel.

If you would like a Building Survey in London or the surrounding areas then please call us at our office on 0208 426 1448.

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