One Benjamin is a new mixed-use address in Farringdon in Central London. Designed by world-renowned architects Alford Hall Monaghan Morris, the building provides 43,562 square ft of office, retail, and residential space.
The original air conditioning design specified four downflow units per floor: two supplying the rear zone of the building and two for the front zone. Each zone was split into two further zones; one supplying cool air towards the perimeter of the building (where it is needed more to combat solar gain), and the other providing warmer air to the central areas of the office space where there is less heat generated by the sun.
AET Flexible Space had built up a strong working relationship with the main contractor, Knight Harwood, while working on a previous project at 20 Soho Square. Having seen the advantages of the AET system on that project, Knight Harwood saw the opportunity at One Benjamin to redesign the original Stage 3 hot/cold aisle design and to implement AET’s underfloor air conditioning solution for the three floors of office space. Knight Harwood felt that AET’s highly flexible system would be more suited to cope with the variations in temperature across the building caused by increased/decreased sunlight.
AET’s underfloor air conditioning systems make use of the space beneath a raised access floor to create the air ventilation path, eliminating the need for ceiling-based services and associated duct and pipework. At One Benjamin, each of the three floors was divided into zones of up to 300m2 depending on the potential use and occupancy density of the area. Each zone is then supplied with chilled or warmed air by a zonal air handling unit or CAM (Conditioned Air Module) and the conditioned air is then delivered into the space using a number of recessed fan terminals (Fantile™).
One Benjamin selected AET’s most flexible system, the CAM-V, which makes use of the raised floor void as a plenum for the distribution of supply air, whilst receiving return air back to the CAM unit at ceiling or high level. With a CAM-V system there is a considerable amount of flexibility in where the fantiles can be placed, allowing for easy reconfiguration depending on the particular needs or layout of an office. For maximum flexibility each fantile is supplied with onboard Fanspeed and Set Point adjustment, but in meeting rooms and cellular space AET offers Flextouch™ wall-mounted controllers which allow users not only to adjust the fan speed and temperature, but also CO2 and humidity monitoring and control.
Headroom Height was a key consideration during the design and build of One Benjamin, and by using the AET underfloor air conditioning system the contractors were able to eliminate much of the ceiling-based services and ductwork. The offices were developed to provide a sustainable workplace, and have been awarded a BREEAM ‘Excellent’ rating. The reduced amount of building materials needed for an AET underfloor system, as well as its long-term flexibility, make it an excellent choice for sustainable building projects.
Overall, AET was able to provide One Benjamin with a high-performing and flexible air conditioning system which was more suited to its needs than the originally proposed downflow system. The building was completed in July 2019 for the Girdlers Worshipful Company and is now beginning to rent its office space and residential units.
AET is the undisputed authority on underfloor air conditioning technology, with over 300 completed projects worldwide and a portfolio of notable world class developments. AET’s system has been used in buildings by Norman Foster, as well as in The Center, Hong Kong’s 5th highest skyscraper, the Willis Building, and numerous other prestigious buildings across the world.
AET was founded in 1993 as a principal worldwide distributor of the pioneering “Hiross” Flexible Space underfloor air conditioning system, taking ownership of production in 2010 under AET Manufacturing Ltd, and developing the AET Flexible Space brand.
AET’s CEO Glan Blake Thomas was instrumental in developing the original Flexible Space “Fantile” and has earned a global reputation as the world’s leading authority on underfloor air conditioning technology and its commercial application.
About the AET Flexible Space Underfloor Air Conditioning (UfAC) System
The Flexible Space underfloor air conditioning (UfAC) system makes use of the space beneath a raised access floor for the distribution of air. This eliminates the need for most of ducting and pipework in traditional air conditioning systems, leading to an average usable space saving of 15%, as well as significant savings on construction materials, installation costs, fit out and reconfiguration costs. The system’s modular and flexible design also minimises waste and energy consumption, a growing concern for both new and refurbished buildings.
With a UfAC system, the floor is divided into zones of up to 300m2 depending on the potential use and occupancy density of the area. Each zone is supplied with chilled or warmed air by a zonal air handling unit or CAM (Conditioned Air Module) and the conditioned air is then delivered into the space using a recessed (Fantile) or floor standing fan terminal.
Air travels back to the CAM for re-conditioning either at floor level via the plenum (CAM-C), or at high level (CAM-V). Both CAM-C and CAM-V systems can be configured to be either chilled water (CW) or direct expansion (DX).