A LEADING US academic has recommended the "selective demolition" of ghost estates and Nama properties that have no value as commercial or residential developments.

The remnants of Ireland's burst property and construction bubble should be demolished in the same way that large parts of the US city of Detroit are being torn down, according to Dr James W Hughes.

Hughes, the internationally renowned Dean of the Edward J Bloustein School of Planning at the Rutgers University in New Jersey, has written extensively about demolition in Detroit and believes the wrecking ball needs to be introduced to deal with one of the biggest problems in post-Celtic Tiger Ireland.

Once one of the most heavily industrialised cities in America, Detroit was the home of the booming US motor industry for much of the last century, but the decline of that industry has left 20% of the buildings in the city empty and dilapidated.

Under a radical renewal plan, large swathes of derelict buildings that blight the city are being demolished with the land due to be returned to agricultural use.

"Things that were unthinkable are now becoming thinkable," said Hughes recently. "There is now a realisation that past glories are never going to be recaptured. Some people probably don't accept that, but that is the reality."

Although he pointed out the significant differences bet­ween the Detroit and Irish examples, he does recommend demolition in Ireland.

"Some buildings may have been built under economic conditions where there appeared to be abundant, seemingly risk-free, cheap global credit that may never return," he told the Sunday Tribune this weekend.

"So some residential estates may never have buyers for the foreseeable future given the overhang of excess inventories. Selective demolition may well be in order if there is no potential of reuse."

He claimed that some empty buildings in parts of Ireland "may still have some economic value in future. The Empire State Building in New York was completed in 1931. It took until 1955 to be fully occupied with private tenants."

Pointing out the differences between the Detroit and Irish examples, Hughes said that Detroit had excessive properties before the current foreclosure crisis in the US.

The downfall started in the late 1960s with race riots and the subsequent 'white flights' to the suburbs. The decline of the auto industry also eroded the city's economic base. This left a massive "depopulated and de-industrialised" city with an array of abandoned, badly aging residential and commercial property that has long lost any economic value.

"Since the city will never return to its past heights, it makes sense to clear large swathes of land and concentrate people in areas that could function as sustainable communities," he added. "Public services could shrink to this new footprint, saving costs, and the vacant land could be used as parks, urban wilderness, or urban agriculture."

Hughes' assessment of the Irish problem comes as it emerged in recent days that the toxic loans agency Nama is prepared to demolish half-completed buildings which it believes have no value as commercial or residential developments.

Nama faces the tough task of dealing with €21bn of work-in-progress assets and deciding what the long-term future of each asset is. Demolition of some sites and returning them to agricultural use is already being actively considered by Nama.