The flexible approach to refurbishment

Following over £5 million of investment, CEG has transformed this two storey office building, constructed in the early 1970’s, to provide a cost effective, high quality office environment with a total lettable area of 160,000 sq ft. Like many buildings of its era, Tricorn House was initially designed and constructed to high standards for its day. However, the perimeter fan coil units had reached the end of their life and their position restricted flexible, deeper plan layouts. The 2.8m slab-slab height also created problems in providing a thermally comfortable solution which could meet tenant expectations.

AET’s underfloor air conditioning system, specified by project Consulting Engineers Andrew Wilkes Management, has provided the low energy comfort heating and cooling air conditioning to all levels from beneath a 175 mm raised access floor. The task was to find a solution that would bring cooling to the inner areas of each deep space floor area whilst permitting the developer to maximise headroom. The duct-free air conditioning and ventilation system plus all cabling and power distribution services are located in the floor void. The result is a 2.5m floor-to-ceiling and a suspended ceiling of only 80mm and a remaining 45mm tolerance for concrete slab sag. This increase in available headroom is fundamental for letting agents and investors who seek to offer the highest quality of space.

Total flexibility

Each floor of Tricorn House is divided into a number of air conditioning zones depending on the potential use and occupancy density of the area, with each zone supplied with chilled or warmed air by a conditioned air module (CAM). The underfloor void is split into supply and return air plena using easily relocatable, airtight baffles. Supply air is drawn up into the occupied space by fan assisted terminal units (FTU450), which are recessed into the floor, plug into an underfloor power source and are connected by data cabling for intelligent control. The building has been systematically refurbished floor by floor as tenants leases have come to an end and the building is now complete. The technology was also applied to the ground floor which has been transformed from a car park and undercroft to a magnificent reception and restaurant area utilising the AET Flexible Space system.

These fan tile units feature individual controls to provide variable speed and temperature adjusted for maximum user comfort. Since they are not restricted by duct or pipe connections, they are easily interchangeable with floor panels in a matter of minutes, allowing easy reconfiguration of the system to accommodate changes in office layout with minimum cost and disruption. Air travels back to the CAM via return air grilles located over the return plenum for re-conditioning and is mixed with fresh air at that point to achieve high standards of indoor air quality.