A novel solution for school renovations: Combining diffuse ceiling ventilation with double skin facade

With the aim to increase today's low retrofitting rate and thus decrease the currently rising energy consumption of the building sector, this work proposes a novel renovation concept for schools. Therefore, two components, double skin facade (DSF) and diffuse ceiling ventilation (DCV), are combined with an exhaust ventilation system, providing an alternative to a traditional renovation where windows are replaced, the external wall is insulated and a balanced ventilation system is installed. Further, based on a Danish case study classroom, different configurations of the novel system, with varying glazing properties and DSF cavity thicknesses are compared against a range of traditional renovations through building performance simulation using IDA-ICE. The results indicate that the new system can achieve up to 11% lower total primary energy consumption as the best traditional renovation while achieving an equal indoor environmental quality and therefore offering designers and engineers a competitive alternative for school renovation projects. Additionally, employing a sensitivity analysis, it could be demonstrated for the primary energy consumption and the global thermal comfort that the glazing (number of panes and physical properties) has a superior influence on the novel system compared to the cavity thickness.