Willis Building

Willis Building

At a glance

  • LOCATION: The City
  • PRODUCT: Fan Coil Units
  • TYPE: Highline 300i Airside
  • QUANTITY: 900
  • CLIENT: British Land
  • CONSULTANT: Hurley Palmer Flatt
  • CONTRACTOR: Michael J Lonsdale


Designed by architect Sir Norman Foster and developed by British Land, Willis Building stands opposite the Lloyd’s building and is 125 metres (410 ft) tall, with 26 storeys. The building features a “stepped” design, which was intended to resemble the shell of a crustacean, with setbacks rising at 97 m (318 ft) and 68 m (223 ft) respectively. In total, there are 475,000 square feet (44,128.9 m2) of office floor space, most of which was pre-let to the Willis Group, a risk management company and insurance intermediary.

Diffusion successfully supplied the building with over 900 Highline 300i Airside fan coil units. Advantages of Airside include:

  • Instantaneous Cooling / Heating
  • More accurate temperature control
  • Easy to commission
  • Easy to maintain