The Crystal, the environmental jewel in London's crown

Print 01 Jun 2015

The Crystal is one of London’s most remarkable buildings. Built and operated by Siemens, the Crystal is a global center for sustainable urban development, setting new standards in environmentally friendly and sustainable buildings. The Crystal gets its name from its architectural resemblance with a rock crystal, another hint at nature. It simply is a world-class center for dialogue, discovery and learning. Innovative techniques have led to what can be considered as the world’s best and largest energy efficient building, an achievement Sapa Building System is proud to have been a part of.

An award winning passive design

The extraordinary shape with many angles and slopes is more than an architect’s dream, it’s the epitome of passive design. Its shape ensures natural lighting and shade and the outer shell of triple-glazing counts 150 controllable façade openings for natural ventilation. Rainwater, as well as graywater and blackwater are collected and purified in the building. 1,580 square meters of photovoltaic panels on the roof take care of all electrical needs.

Heating is provided by heat pumps operating on a 17 kilometer long underground piping system. All these measures have earned the building “Platinum” LEED certification (Leadership in Energy and Environmental Design) and a BREEAM outstanding certification (Building Research Establishment Environmental Assessment). The Crystal is the first and only building in the world to receive the top rating in both certification systems.


Electricity from the rooftop photovoltaic system covers roughly 20% of the total electricity demand, enough for operating the ground source heat pump. Additional electricity is provided by wind power from the London Array off-shore wind farm and hot water is produced by thermal solar panels. All in all, the 6,300 square meter building consumes 46% less energy and emits 65% less carbon dioxide than comparable office buildings. Crystal’s users and visitors can see the latest energy and water consumption figures on Green Building monitors, motivating them to adopt the same sustainable practices.

The Sapa contribution

The Siemens Building Technologies Division has heavily relied on Sapa Building System products and knowhow in order to reach these high levels of energy efficiency. For this specific project, Sapa Building System conceived and developed all automated parallel opening windows in the complex façade by Waagner Biro, allowing ventilation air gaps of up to 400mm. This was no small feat considering the nature of the buildings design. There can be no doubt, Sapa Building System have strongly contributed to aiding the Crystal’s extremely high energetic and environmental goals.