Indoor Environment Factors affecting Residents’ Satisfaction

1. Indoor Environment Factors affecting Residents’ Satisfaction Sung Ku, University of California, San Diego, Urban Studies and Planning Program FINDINGS & ANALYSIS Certification Criteria of Indoor Environment in LEED and Green Globe rating system ABSTRACT In this research project, current green building rating system are evaluated with a perspective of satisfaction of occupants. Majors factors related to indoor environments are extracted and analyzed how much these rating systems reflect human health factors. To know how these factors are reflected to current green buildings, a survey was carried among the occupants of a high rated green building to investigate perceived importance and satisfaction of each factor. Results showed that there were factors that had gaps in between importance and satisfaction, which tells us that indoor environment factors are not considered enough by these rating systems. CONCLUSION Indoor environment factors evaluated by current LEED certification does not fully reflect residents’ expectations and satisfactions. Results of the survey showed that satisfaction of factors which were indicated important was low. Exterior noise, thermal comfort, and indoor air quality should have more emphasis in the rating system. Since these indoor environment factors are not emphasized in current rating systems, based on our results, we insist that there should be more discussion on these factors in future revisions of these rating systems. In this work, human health related indoor environment factors are being focused. While LEED v2.2 has 19% of indoor environment factors, Green Globes has 16%. LEED and Green Globes rating systems have different scoring weights and points in Indoor Environment Quality (IEQ). LEED emphasizes Low-Emitting Material while Green Globes emphasizes Effective Ventilation. Acoustic Comfort is only considered by Green Globes weighing 13% of indoor IEQ factors. Importance and satisfaction of indoor environment factors • RESEARCH QUESTIONS • Do the current authorized rating systems of LEED and Green Globes satisfy the needs of residents of green buildings on indoor environment? • If not, what factors do the residents think of as important matters for indoor environment? • Research Design and Methods • By considering the demands of occupants, LEED and Green Globes rating systems are analyzed to find the main factors affecting indoor environment of green buildings. • Indoor environment factors in both systems are compared based on what the indoor occupants consider important. • Green building rating systems are evaluated by paper research and field survey using questionnaires. Green building occupants were also interviewed. Survey results show that there is difference between importance and satisfaction for each indoor environment factor. Although the building is rated Gold by LEED, there are gaps between importance and satisfaction of exterior noise, thermal environment, and indoor air quality. This means that the residents of that building feel the need for improvement on these factors. Also, we can see that the duration of sunshine, prospect view, and landscapes are considered important to the residents. However, both two rating systems do not weigh these factors enough.