Property: Shoreditch meets City as beach ball comes to rest on Silicon Roundabout

A giant beach ball has been tethered to the roof of an empty building on Old Street roundabout.

The 10-metre diameter sphere marks the spot of a £200 million development by Derwent London. They say a planned 15-storey tower will save 180 giant beach balls full of CO2 each year compared with a conventional block.

Nice gimmick. But what’s nicer is the 228,000-square-foot “white-collar factory” is designed by architects AHMM to attract big Tech-centric tenants happy to pay between £40 and £50 per square foot for high-ceilinged space.

The feel on Wednesday during a tour with Derwent’s development director Simon Silver was Shoreditch-meets-City. Two floors have been lost on the 70-metre tower because the ceilings are 3.5 metres high instead of the conventional 2.5 metres. Development manager Benjamin Lesser says the £180 per square foot build cost is 10% to 15% lower than a conventional “sealed box”. Silver says the saving on £75 million construction bill “compensates for not building the extra floors.”

Derwent London is expecting to make the normal 20% margin. If they do that, David Cameron should cut the ribbon. In November 2010 the Prime Minister designated the un-magical roundabout as the western nexus of Britain’s new “silicon valley,” running down to Stratford. How we all laughed.