A first application of the Lightsolve approach: Pre-design of the new Belgian VELUX headquarters

This study presents the application of the “Lightsolve” method on the pre-design of a new sustainable building in order to optimize its daylighting. At the time of the project, this method combined climate-based illuminance and glare evaluations with visual renderings. Illuminances were presented according to a goal-oriented approach and glare was evaluated through the DGP. Both were displayed on temporal maps. The Lightsolve method was used to size lateral and zenithal openings and shading devices. A first conclusion of the study is that it is necessary to couple daylight metrics with a solar gain metric. Comparison between Lightsolve and daylight methods used in rating systems showed that these ones do not give enough accurate information for optimizing the daylighting design. Designer’s satisfaction evaluation showed that the goal-oriented approach and the temporal map representation were appreciated although this latter was rather difficult to understand. It also showed that an expert tool should be proposed in order to help designers to analyse their results. Finally, it was pointed out that the quality of daylight should be evaluated in Lightsolve, which will be done through a PhD work.