Gilbert-Ash confirms £40m RIBA HQ revamp deal

The Grade II* listed building is undergoing a major refurbishment and restoration as part of RIBA’s wider House of Architecture programme, with construction scheduled for completion in September 2027. The project will focus on modernising the 1930s headquarters while retaining its historic character.

Works include the replacement of ageing building services and improvements to the building’s external envelope to increase energy efficiency and address water ingress. The scheme will also introduce improved accessibility, fire-safety measures and upgrades to the building’s environmental performance and facilities.

A new fully accessible entrance will be created on Weymouth Street, alongside new exhibition and events spaces. The refurbishment will also give greater prominence to the building’s café and shop, helping transform 66 Portland Place into a more accessible public destination.

The project is being delivered as a pilot for the UK Net Zero Carbon Buildings Standard, placing retrofit, energy performance and carbon reduction at the centre of the refurbishment.

Purcell is acting as architect for the delivery phase, with Gardiner & Theobald as project manager, Jackson Coles as quantity surveyor, Eckersley O’Callaghan as structural engineer and Harley Haddow as services engineer.

The project highlights the growing role of retrofit in upgrading London’s historic building stock while improving energy efficiency, accessibility and long-term performance.