One in seven of England’s 9,300 conservation areas is at risk, according to English Heritage, suffering from neglect, decay and damaging change.

Launching a campaign to save the nation’s neighbourhood heritage, EH chief executive Simon Thurley said that in the first ever survey of conservation areas as part of compiling the Heritage at Risk register, among the worst perpetrations was the use of plastic windows of doors, which has affected 83% of conservation areas.

“People think that by using plastic, or UPVC, windows and doors they are saving the planet” he said. “There’s no evidence that they save energy, they look wrong, and while they are supposed to last 50 years they won’t last for more than 20 and many will have to be replaced after seven.”

Other key issues are badly maintained roads and pavements, street clutter, loss of front garden walls and hedges, unsightly satellite dishes, the effects of traffic calming, alterations to house fronts and roofs, and unsympathetic extensions.

“Problems fall into two main areas: what owners do to their properties and what councils do or fail to do to the streets, pavements, parks and public spaces” he said.

He called on councils to make more use of guidelines to advise on protection of details, to get council departments to work together to improve public areas, and to get local people involved through civic societies and residents;’ groups.

Thurley also announced that the winner of the national award for local authorities which have done most to improve their conservation areas is Stockton-on-Tees.