The unusually shaped building has a total area of around 52,000 sq. ft. and is currently undergoing full structural reconfiguration and refurbishment to form larger, open plan floor plates and Cat A office accommodation with a floor to ceiling height of 3.3m to be created on floors three to seven. Space saving underfloor air conditioning has been specified by Consultants WPP and Architects Buckley Grey Yeoman.

With underfloor systems, fully conditioned air is fed into the plenum by zonal downflow units (CAM), which is then supplied into the workspace via fan terminal units (Fantile). The fantile units feature integrated controllers where users can personally adjust fan speed and temperature to suit their own comfort. Systems can be configured with underfloor or high level return and can easily integrate with passive or other ventilation systems.

The system specified for 33 Glasshouse Street is a CAM-C Direct Expansion system with supply and return air distributed via the floor plenum. The Fantiles supplied are slimline TUS-EC fan terminals, designed to fit into the shallow floor plenums common in London refurbishments and with EC motors for enhanced energy efficiency. Instead of a rooftop chiller providing chilled water, the building will be using Daikin Heat Pump units to maximise use of space and energy efficiency.