Harella House, Clerkenwell | Case Study | AET Flexible Space

Case Study

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Harella House

Clerkenwell, London, UK

This high-end refurbishment and extension of a 1930's warehouse and former clothing factory has had its interior space transformed into six floors of premium, light, airy, and flexible workspace, whilst also achieving a BREEAM ‘Excellent’ rating.

Total Area

3,107 m2

CAM-C Floor supply, floor return & CAM-V Floor supply, high level return level return

2020 Energy Efficiency Refurbishment

Completed in June 2020, the high-end refurbishment and extension of this 1930s warehouse and former clothing factory has transformed its interior space into six floors of premium, light, airy, and flexible workspace.

Harella House has received a BREEAM ‘Excellent’ rating, and it is estimated that the refurbished building achieves a 47% reduction in carbon emissions.

The ceiling heights and original windows were key features to be preserved during the refurbishment, and one of the key advantages of AET Flexible Space’s underfloor air conditioning system is that all equipment can be installed beneath the existing raised access floor, and there is no need for a lowered ceiling.

Reducing the building’s energy consumption and carbon emissions were key considerations for this project, and AET Flexible Space’s underfloor air conditioning system was selected for its low environmental impact and high efficiency. All heating and cooling in the building is provided by a high-powered heat pump system.

Working with the architects, Piercy&Company, and consultant, Elementa Consulting, AET specified its CAM-C underfloor air conditioning system. AET’s CAM-V system and TU350 slimline Fantile™ units were later specified for the fourth-floor mezzanine. The slimline Fantiles™ were specified on the mezzanine level to accommodate the very low floor void, and allow for maximum floor to ceiling heights.

Across all floors, chilled or warmed air is provided by the conditioned air module (CAM). The underfloor void is divided into supply and return air channels, and supply air is drawn up into the space by Fantile™ units. Air travels back to the CAM via return grilles, which are located at floor level with the CAM-C system, and at high-level for the CAM-V system, where it is reconditioned and is mixed with fresh air to achieve high standards of indoor air quality.

The internal layout for Harella House needed to be as flexible as possible, which was another reason why AET’s underfloor air conditioning system was specified. AET’s Fantiles™ are recessed into the 240mm floor plenum, and can easily be moved and repositioned, depending on changing office layout. This gives the end-users of Harella House increased flexibility and control over their workspaces, without the costs associated with repositioning fixed, ceiling-based systems.

Developer – Chait Investment Corporation Ltd

Architect – Piercy&Company

M&E Consultant – Elementa Consulting

Quantity Surveyor – Exigere

Main Contractor – BW Workplace Experts

M&E Contractor – Indoor Climate

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