Best Structural Innovation

Guy’s and St Thomas’ hospital trust was after “a hospital that does not feel like a hospital” – and that’s exactly what the design team gave it, despite some awkward structural challenges. For starters, the site of the hospital was bounded by the River Thames on one side and a road on the other, and then there was the question of how to make the huge curving glass roof structurally sound without compromising the design. Finally, the team had to make sure a 20 tonne fire engine would be able to access the building from below …

The finalists

Redrow Homes: Altolusso Apartments, Cardiff

Altolusso – Italian for “high living” – is a fitting name for these 292 apartments, which are not only the ultimate in luxury but also make up Cardiff’s tallest residential tower. But it’s the structural challenges that were overcome by the crack team of Redrow, Laing O’Rourke, Holder Mathias Architects and Arup that really impress. First, a retained Victorian facade was used to create a three-storey foyer with a glass atrium. Second, because of the height and the complex three-leaf clover footprint, special wind flow studies had to be carried out. The result is not only an efficient structure that blends futuristic design with traditional features, but a project that has played a key part in the regeneration of a city where you can now truly lead the high life.

Capita Percy Thomas:Wales Millennium Centre

When it comes to putting foundations down, Cardiff Bay is a far from ideal site for any building, let alone one that involved more than 5000 tonnes of structural steel for a floor area of more than 33,000 m2. One of the first problems identified was pockets of soil contamination. Worse, the first 10 m of soil was soft alluvium, which could cause settlement. And as an added headache, the water table was 3 m below and former docks structures were discovered. The solution was to reuse existing dock walls while placing 25 m piles for extra support. And above ground, the Wales Millennium Centre is protected by a stainless steel airtight roof that can withstand the strong south-westerly wind and enhances the acoustic performance of the theatres within. Another great addition to the Welsh capital.