10 Facts about the Willis Building

Completed in 1975, the Willis Building in Ipswich redefined the modern office with its open-plan design, flexible layout and employee-focused amenities. Accommodating 1,350 staff across three-storeys, the project fostered a strong sense of community whilst seamlessly integrating into the surrounding urban setting.

Learn more about one of the practice’s earliest projects, from its secret swimming pool to its innovative use of raised floors which anticipated the digital age and the importance of technology within the office.

1. The building was officially opened on June 2, 1975, by former Prime Minister Harold Macmillan.

2. In 1991 the Willis Building was recognised as the newest building to be given Grade I listed building status in Britain. At the time, it was one of only two listed buildings under 30 years of age.

3. The original design featured a swimming pool for employees. This has since been preserved and covered up to facilitate more office space, however it can be seen underneath the false floor.

4. The design introduced raised office floors, anticipating the revolution in information technology. This allowed Willis Faber to implement computerisation with minimal disruption, unlike many of its rivals who had to relocate.

5. The building features a suspended glass wall that stretches 304m, which is nearly the height of the Eiffel Tower.

6. Efficiency was a key consideration for the 1,350 employees that the design could accommodate. To enhance accessibility, escalators were installed in the three-storey building, despite them typically being used in larger multi-storey structures at the time.

7. The building’s solar-tinted curtain wall appears almost black during the day, reflecting Ipswich’s historical buildings that surround it. However, at night, the glass appears transparent and reveals the internal design.

8. The project is an early example of energy conscious design, heated by natural gas with a deep plan and insulating grass roof to ensure good overall thermal performance.

9. Foster + Partners (then known as Foster Associates) was appointed to design the Willis Faber building in 1991, making it one of the practice’s earliest projects to date.

10. The design has accumulated various awards including the RIBA Award, RIBA Trustees Medal and the Test of Time Award Commendation for the British Council for Offices.