VIRTUS LONDON2 (Hayes) Data Center, United Kingdom

Tetra Tech’s High Performance Buildings Group provided mechanical, electrical, fire protection, communications, security, and vertical transportation services for the VIRTUS LONDON2 (Hayes) data center.


  • Size: 6,200 square meters (66,736 square feet)
  • Construction Cost: CIC
  • Client/Owner: VIRTUS
  • Architect: RPS
  • Contractor: Bouygues group
  • Completion Date: 2014


The data center has been designed to provide more than 6,200 square meters (66,000 square feet) of 18 megawatts of high-efficiency, best-in-class data center space.

London-based data-center company VIRTUS called upon the mission-critical expertise of Tetra Tech to design its LONDON2 Data Center in Hayes, West London.

The brief from VIRTUS was clear: to provide a flexible, cost-effective data-center space that was extremely energy-efficient. VIRTUS had a clear objective to achieve a load density of up to 2 kilowatts per square meter at a very low Power Usage Effectiveness (PUE) using a Tier III topology to provide over 6,000 square meters (65,000 square feet) of data hall space.

The use of indirect fresh-air cooling supplemented by adiabatic cooling was key to underlining energy efficiency at Hayes. The subsequent lowering of the load-to-site energy ratio means VIRTUS will now have more power to use, or capacity to spare, adding to the flexibility of its offering.

To maximize infrastructure capacity and efficiency, the following strategies have been deployed:

  • Indirect adiabatic cooling of the data halls
  • Hot aisle containment
  • High-efficiency self-scaling uninterruptible power supply (UPS)
  • Direct/indirect fresh-air cooling of plant rooms
  • Naturally cooled transformers
  • High-efficiency data hall lighting with absence detection
  • LED lighting in offices and circulation routes
  • Photovoltaic array

Other initiatives included:

  • An integrated communication network
  • A borehole water supply
  • Intelligent patching
  • A data center infrastructure management (DCIM) monitoring system

Image courtesy of C/VIRTUS, UK