They may be mistaken for frosted glass or even the kind of sheeting found on sheds but the translucent triangles on top of Crossrail Place are cleverer than that.
They remain both taut and plump because they are, in fact, highly insulating plastic pillows filled with air under pressure. More lilo than double-glazing. They are made of Ethylene tetrafluoroethylene (ETFE) which can withstand a range of temperatures without corrosion.
Foster+ Partners say: "Providing a warm, natural counterpoint to the steel and glass towers of CanaryWharf, the wooden structure evokes the ships that once sailed into West India Dock. The spruce glulam beams are sustainably sourced and support ETFE cushions, which are filled with air and lighter than glass."
The length of the roof is longer than One Canada Square is tall.
The roof sits above a roof garden containing plants from places in the world connected to London via the West India Docks (hence the empty triangles for ventilation and rain).
Below that is Canary Wharf Group’s four storey, 115,000 sq ft retail and leisure development including shops, restaurants, bars and a cinema.
Work began on the new station in May 2009 by creating a 250m long and 30m wide watertight dam in the waters of North Dock, using an innovative “silent” piling method to avoid disturbing the neighbours.
The station box was then built top down, 28m below the water surface to create the ticket hall and platform levels. The station has now been fitted out and handed over to Crossrail to complete. Trains will run through from 2018.