Council for Aluminium in Building

The Crystal

Project The Crystal (Siemens Urban Sustainability Centre)
Location London
Sector Office / Commercial
Project value £30m
Architect Wilkinson Eyre Architects
Main contractor ISG
CAB member WindowMaster Control Systems


The Crystal (Siemens Urban Sustainability Centre) is divided into a series of sectors or ‘crystals’. A mixed-mode ventilation strategy was specified so that, where seasonally possible, the office and exhibition is naturally ventilated using opening vents in the facades and roofs.

WindowMaster designed a system offering precise and intelligent three-speed control of 91 rooflights using 182 chain actuators. Intelligent control is provided by 24 MotorLink® panels which give two-way communication and position feedback to the Siemens BMS, allowing control and three-speed operation of rooflights through a KNX bus. The whole system is programmed by the BMS integrator.