A leading property barrister has become embroiled in a row with neighbours over an extension to his £1.8million home that could land him in trouble with the town hall.

Ham & High: The �1.8million house at the centre of the row. Picture: Nigel SuttonThe �1.8million house at the centre of the row. Picture: Nigel Sutton (Image: � Nigel Sutton email pictures@nigelsuttonphotography.com)

Philip Galway-Cooper has dealt with all kinds of neighbour disputes, including arguments over boundaries, party walls and construction, in a 21-year legal career.

But now he and his wife Wendy have infuriated many of their own neighbours by building an extension at the back of their home in Gayton Crescent, in the heart of the Hampstead conservation area.

Several have complained that the project was carried out without planning permission – and are urging Camden Council to act.

David Stone, 43, who lives in Grade II listed Willow Cottages, behind the house in Willow Road, said: “The place has been a building site for five years.

“Substantial work has gone on without approval in a conservation area. They’ve built a four-storey extension that looks directly into our houses and gardens, all unapproved.

“This is an issue of public concern. When local heritage is lost, you very rarely get it back again.”

The house was shrouded in scaffolding and plastic sheeting while work went on from 2008 to 2013.

As well as being frustrated that the build dragged on for so long, neighbours say they were shocked to discover the full extent of the work when the scaffolding came down in November.

Art gallery director Selina Skipwith, 41, also of Willow Cottages, said: “It’s been just constant disruption, as well as being an eyesore. It does not fit in with the conservation area.”

But Mr Galway-Cooper said the work was carried out under permitted development rights, so no planning permission was required.

He said council planning officers assured him on several occasions that the works were lawful, adding: “Applications have been made to the council to certify this and we are awaiting the outcome.”

Camden Council is weighing up whether the works are within the permitted development rules.

A decision is imminent and if the council rules against the Galway-Coopers, they will be forced to tear down the extension.

Cllr Phil Jones, cabinet member for planning, said: “If permission is refused, then formal enforcement action will be taken.”