Development of the CoSIE Lab: An advanced laboratory for multi-domain indoor environmental quality research

Laboratory studies are essential in advancing multi-domain indoor environmental quality (IEQ) research, as they provide highly controllable, precise, and reproducible conditions for investigating the effects of various IEQ factors on occupants’ health and behavior. However, many existing IEQ laboratories face significant challenges, including inadequate multi-domain control, limited participant-laboratory interaction, and incomplete performance testing. This paper presents the comprehensive development process of the Comfort Studies and Indoor Environment Laboratory (CoSIE Lab), a flexible and expandable research facility designed to control IEQ factors across thermal, indoor air quality, visual, and acoustic domains. The development process is organized into distinct phases: conceptual planning, design and construction, commissioning and performance testing, and experimental applications. Through this structured approach, we aim to share valuable insights and lessons learned from the development of the CoSIE Lab. Key findings indicate that capillary tube mat is an effective solution for radiant temperature control. In conjunction with a hydronic system, the CoSIE Lab achieves 76 zones with individual surface temperature control ranging from 15 °C to 40 °C. The surface radiant system enhances air conditioning process, enabling both homogenous and heterogenous air temperature distributions within the test rooms. Measurements of illuminance and color temperature demonstrate close alignment with design specifications for artificial lighting as simulated in software. An acoustic assessment reveals potential overestimation of effective absorption areas when applying the DIN EN 12354‐6 model for reverberation time calculations. In addition to these findings, this study contributes to enhancing clarity and consistency in research dissemination related to IEQ laboratory developments.