EMPTY units in shopping centres built in the 1960s and 1970s have reached an abnormally high level, a study has revealed.

The report, which looks at the shopping centre market since 1965, highlights the difficulties that property companies in the region face in finding tenants.

Planning consultants CB Hillier Parker found shopping centre vacancy rates have reached an all-time low of five per cent.

But when it comes to older malls, considered concrete eyesores by many shoppers, the figure is more than seven per cent.

Chris Goddard, head of retail planning at CB Hillier Parker, said the study points to tough choices for council planners and mall owners.

"It is often much easier to extend a town centre, rather than trying to justify the redevelopment of existing retail space," he said.

The Festival Walk precinct at Spennymoor, in County Durham, has been plagued by vandals and has several boarded-up units.

Claire Luck, owner Retail Properties' property manager, admitted that it was hard work attracting tenants.

"In Spennymoor, in particular, the vandalism is a problem, because we end up spending money on repairs when we would like to spend it on doing up the place.

"Really it is just trying to convince people that it has potential," she said.

The firm was in talks with two possible tenants which could act as "anchors" and had had interest from other businesses as a result.

Cheryl Williamson, senior lecturer in property management at Northumbria University, said the ugly design of the buildings did not necessarily deter shoppers.

"The location is more important - that it is easy to get there by car and public transport, and that there is the right mixture of tenants," she said.

Les Southerton, chief executive of Middlesbrough Town Centre Company, said one of the problems 1970s malls faced was that the units were usually 1,000sq ft.

"Most modern retailers are looking for units of between 3,000 and 4,000 ft.

"Legal and General, the owners of the Cleveland Centre, are working on a package of proposals to improve the configuration of the centre."