Townley Grammar School for Girls, Bexleyheath
The extension of existing facilities including a Performing Arts Hall, Sports England, Sports Hall, Changing Facilities, six Laboratories and IT Room.
Sustainable Design: the building is designed to be predominantly naturally ventilated through the design of stack ventilators and maintaining thermal mass to the internal environment.
A performance hall is passively cooled via a ground coupled ventilation system maintaining comfort for up to 300 occupants. Air is passed through pipes encased in concrete and located 800mm below ground level. The system cools air prior to entering the hall during the summer period and pre-heats air during the winter months.
A detailed thermal analysis informed the client and design team of the need for passive control of solar gain and ventilation systems. Solar control is provided in the form of photovoltaic shades incorporated onto the south facing facade.
Building Analysis: during the concept stage of the architectural design, thermal analysis and computerised fluid dynamics confirmed the nature of building form, fabric and passive controls necessary to maintain a comfortable internal environment. Hall areas both general purpose and in this case task specific, have periods of high occupation. Under these circumstances, it is important that comfort is maintained which through detailed thermal analysis was achieved well within the required criteria. The bespoke design of a ground coupled cooling system improved comfort, minimal CO2 emissions and life cycle costs.