Dynamic Daylight: Measuring the impacts of high performance daylighting system on occupants health, satisfaction, and productivity

摘要

The aesthetic and functional appeal of high performance all-glass buildings is daunting. It creates a hyped expectation of better daylighting performance and improved indoor environmental quality (IEQ) that is typically hypothesized to improve occupant's health and productivity. Despite the favourability of this hypothesis, most recent studies have failed to prove these linkages leading to non-conclusive evidence of all-glass building performance and specifically green and LEED certified ones. Most previous studies point to glare perception, uneven daylight distribution, as well as acoustical problems for the open-office common of all-glass buildings that try to maximize daylight penetration within the occupant's work space. In addition, methodological deficiencies in quantifying occupants' experience as well as comprehensive measurements of physical and behavioural environmental factors in an integrated and comparative approach have also limited the applicability of previous studies to guide practice. The specific question of this project is whether a well-designed all-glass office building envelope with sufficient shading, occupant's controls, and acoustical design could achieve daylighting autonomy while managing glare and acoustical comfort leading to increased occupant's well-being, health, and productivity. To achieve this a well-planned evaluation study with pre-post occupancy analysis of a progressive organization's move from a traditional cellular office building with punched walls to a state-of-the-art all green-LEED™ certified office building was conducted for one year pre-move and one year post-move. This paper reports on a longitudinal assessment of a commercial high performance LEED™ platinum retrofitted building. The buildings houses 800 employees working within 270,000 square feet of open-concept office space. The state-of-the-art facility was designed to promote cross-collaboration. Sweeping views of nature and daylight are possible from 92 percent of the interior space. Continuous and intermittent measurements for dynamic daylighting metrics, visual and acoustical comfort, as well as a pre-/post-occupancy evaluation occupants' surveys were conducted. Results show strong correlations between improved visual comfort daylight variability of the retrofitted green environment that is well correlated with improved employees' productivity and satisfaction. Lessons learned and recommendations for future applications of the systems employed are discussed.