The first of its kind and a truly remarkable feat of engineering, a transparent swimming pool spans between two apartment buildings ten storeys in the air.

A breathtaking, suspended swimming pool named ‘Sky Pool’ will be unveiled for Embassy Gardens – the residential heart of London’s newest neighbourhood, Nine Elms on the South Bank. The transparent outdoor pool will link two residential buildings at the 10th storey – a world first – and allow residents to swim from one building to the other.

Eckersley O'Callaghan were presented with some significant challenges in engineering the structure of the pool. It has a clear span of 15 metres between two buildings 35 metres above the ground. Without any supporting steelwork, the pool is required to take a load of 165 tonnes of water.

The side walls form deep beams capable of spanning the length of the pool, while carrying the weight of the water, and dealing with water pressure and wind loads.

Meanwhile, the two buildings are subject to inherent environmental movements such as wind sway and foundation settlement. The new structure must adapt to these forces, meaning it cannot be rigidly connected at both ends; it must be allowed to slide at the same time as maintaining watertightness.

In collaboration with US polymer technologists, we have designed a bonded acrylic structure, resulting in less intrusive joints and connections and greater transparency. The refractive index of acrylic, being closer to that of water, will also produce much less distortion when viewed from in the water or from outside.

London, UK

Ballymore Group

HAL Architects | Arup Associates