Refereed Paper A SIMULATION DESIGN STUDY FOR THE FAÇADE RENOVATION

Office buildings with large glass facades often face problems such as glare, thermal discomfort, overheating and increased energy demand. In this case study, thermal and daylighting simulation were performed in order to investigate the possible options for the facade renovation of a large office building in Montreal. For the daylighting part, the available daylight on the work plane surface of interior perimeter zones was calculated for each façade, considering several shading options: dark screens, roller shades with variable properties, reflective venetian blinds, translucent glazings and combinations of the above. Daylight rendering with and without shading helped in visualizing the results. The impact of different shading properties on glare was also studied, as well as the impact of window size on annual daylight autonomy for each case. For the thermal part, emphasis was given on the effect of shading location, properties and control on the thermal loads, since the glass facades account for a big part of the load. It was found that the shade location and properties have a significant impact on heating and cooling load as well as on the thermal comfort near the windows. The simulation results showed that a 60 % reduction in cooling demand – due to the façade- could be achieved, if controlled shades with small or variable transmittance and high outside reflectance will be used