Daylight autonomy and facade design : From research to practice for the Stockholm SEB Bank head office

Glazing-to-wall area ratio (GWAR) is one of the key parameters determining energy use in office buildings. Excessive fenestration areas not only yield significantly higher energy use, they are often associated with glare problems yielding a wasteful solution, where blinds are down while electric lighting is on. Future near-zero energy office buildings will have a reasonable GWAR to optimize the balance between good daylighting and low heating and cooling loads while providing a satisfying work environment with good view out. Starting from this evidence-based knowledge, White arkitekter developed innovative building facades for the SEB Bank headquarters in Stockholm, using advanced parametric modelling, where glazingto-wall ratios were optimized as a function of orientation. Other aspects of the design included: 1) adaptation of building functions in relation to orientation to avoid glare, 2) use of self-shading principles adapted to orientation, 3) increase of the window-head-height to maximize daylight penetration, 4) tri-dimensional angulation of facade elements allowing diffuse indirect daylight reflections and intermediate light transitions, 5) modulation of GWAR according to floor level. This paper presents the innovative architectural design proposal and discusses the process used to translate the evidence-based knowledge into an innovative building design using parametric modelling supported by advanced simulation and modelling tools.QC 20190923