Diagonally arranged louvers in integrated facade systems - effects on the interior lighting environment

Abstract

Building facades play an important role in creating the urban landscape and they can be used effectively to reduce energy usage and environmental impacts, while also incorporating structural seismic-resistant elements in the building perimeter zone. To address these opportunities, the authors propose an integrated facade concept which satisfies architectural facade and environmental design requirements. In Europe, remarkable facade engineering developments have taken place over the last two decades resulting in elegant facades and a reduction in environmental impact; however modifications are needed in Japan to take account of the different seismic and environmental situations. To satisfy these requirements, this paper proposes the use of a diagonally disposed louver system. Diagonally arranged louvers have the potential to provide both seismic resistance and environment adaptation. In many cases, louvers have been designed but not installed due to concerns relating to restricted external sight lines and low levels of natural lighting in the building interior. To overcome these problems, full-scale diagonally arranged louver mock-ups were created to evaluate illumination levels, the quality of the internal daylight environment and external appearance. Interior illumination levels resulting from a series of mock-up experiments were evaluated and correlated with results from a daylight analysis tool.