SAS International supplied both passive and active Integrated Service Modules (ISMs) to the Police Federation of England and Wales’ Headquarters in Leatherhead, Surrey. The design brief demanded that the building utilise energy efficient technologies to meet the Police Federation's ongoing commitment to embracing sustainability within its buildings.

The M&E services for the contemporary two-storey building were designed by Environmental Building Services Consultancy, Couch Perry Wilkes. SAS International installed the ISMs incorporating active chilled beams and bespoke flat modules of behalf of mechanical and electrical contractors EMCOR.

"The Police Federation was keen to embrace the low energy proposals and sustainable design put forward by the design team. The SAS chilled beams and Integrated Beams provided an ideal solution for some important areas," commented John Hauton, Mechanical Associate Director for Couch Perry Wilkes. "They have interfaced well with the exposed slab principle and provided a good quality finish to these high profile areas. SAS have developed some bespoke units, on budget, that suit the specific needs in these keys areas and we would happily use them again."


The active ISMs provide between 700 and 800 Watts per linear metre (W/m) of cooling and approximately 550 W/m of heating. Additionally fresh air is supplied at a rate of 12 litres per second per person.

The passive ISMs provide 185 W/m of cooling, with room air velocities of less than 0.25 metres per second. The flow and return water temperatures, for both passive and active beams, are 14°C and 17°C respectively.

The higher the temperature differential between the air in the occupied space and the water flowing through a chilled beam, the greater the amount of cooling provided. This is particularly important during peak summertime temperatures, when the temperature differential is greatest.

In this project the ISMs are found throughout the building's offices, meeting rooms and chairman’s office, offering a sleek and attractive feature incorporating building services, such as smoke detectors, PIR sensors and both up and down lighting.

ISMs are compatible with free cooling and ground sourcing systems, further reducing the need for mechanical cooling. Night purging is used at the Police Federation's Headquarters to pre-cool the exposed mass during the summer months, helping to reduce the amount of energy required.

Due to their inherent energy efficiencies, ISMs can help towards achieving higher EPC (Energy Performance Certificate), DEC (Display Energy Certificate), BREEAM and LEED ratings.

In addition to the ISMs, solar panels, part condensing boilers, part atmospheric boilers and roof-mounted air handling units are among the M&E features found at the building. The new Police Federation HQ has been designed to incorporate offices, conference and training facilities for Police Federation representatives and members as well as hotel facilities. The hotel includes 55 bedrooms, a high spec leisure centre, cafe bar, restaurant and lounge area.