The biggest premium versus low-rise neighbouring flats was 68 percent for the 43rd floor of the 525-feet tall Strata tower, London's tallest residential tower in the Elephant and Castle district, an area set to benefit from a facelift in coming years.

"Unlike the high-rise blocks of the 1960s, tower developments now symbolise luxury living and can add substantial value," said Jennet Siebrits, head of residential research at CBRE (CBG.N),adding interest from southeast Asian investors had driven prices.

Fuelled by demand from overseas investors looking to shield wealth from the euro zone crisis and Arab spring uprisings, prices for the best central London homes rose 39.5 percent between a post-recession low in March 2009 and last November, property consultancy Knight Frank said.

The CBRE study, which looked at 1,226 apartments in six towers, found prices rose an average 1.5 per cent per floor.

The Strata will be overtaken this year by the Shard skyscraper next to London Bridge as the building housing London's highest homes, with 10 penthouses near the top of what will become western Europe's tallest tower at 1,016 feet.

(Reporting by Tom Bill; Editing by Dan Lalor)

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