Hackbridge Primary School
This exemplar project involves the creation of a new build primary school which will provide space for 420 pupils aged 5-11. The school is being designed to be net zero carbon (regulated and unregulated), zero primary energy and Passivhaus certified. It will be a highly sustainable environment to learn in and an environment to learn from. Careful consideration has been taken to select materials that are healthy, have low embodied energy and be easy to construct and maintain. The internal environment is developed to maximise natural day lighting and fresh air provision.
The scheme is benefitting of its location next to the BedZED project and also adopts One Planet Living aspirations. To achieve zero carbon and Passivhaus a rigorous approach has been adopted first to reducing energy consumption through very high insulation levels, low air permeability and well considered junctions to minimise thermal bridging. Thereafter a robust strategy for implementing enough Zero carbon technologies (LZCs) to provide a net zero carbon school.
Once energy consumption is reduced using PassivHaus methods achieving a net zero carbon building becomes more realistic through the use of on site renewables. In this instance, we propose to achieve this through an extensive array of high efficiency solar PVs and a reverse cycle ground source heat pump system with the potential for inter-seasonal thermal storage to boost the systems ‘coefficient of performance’. Off site renewables are not required.
The school will have no fossil fuel gas supply (using induction hobs in the kitchen) to avoid any combustion flue products from the site. The building will have a single high efficiency central air handling unit to provide mechanical ventilation to classrooms in winter. In mid season the windows are openable by staff for controlled ventilation and then in peak summer, to avoid potential issues with global warming in future years, the mechanical system can operate in conjunction with cooling from the reverse cycle heat pump (which through the thermal storage increases the winter time performance).