The Spatial and Temporal Variability of the Indoor Environmental Quality during Three Simulated Office Studies at a Living Lab

Abstract

The living lab approach to building science research provides the ability to accurately monitor occupants and their environment and use the resulting data to evaluate the impact that various components of the built environment have on human comfort, health, and well-being. A hypothesized benefit of the living lab approach is the ability to simulate the real indoor environment in an experimentally controlled setting over relatively long periods of time, overcoming a significant hurdle encountered in many chamber-type experimental designs that rarely reflect typical indoor environments. Here, we present indoor environmental quality measurements from a network of sensors as well as building system design and operational data demonstrating the ability of a living lab to realistically simulate a wide range of environmental conditions in an office setting by varying air temperature, lighting, façade control, and sound masking in a series of three human subject experiments. The temporal variability of thermal and lighting conditions was assessed on an hourly basis and demonstrated the significant impact of façade design and control on desk-level measurements of both factors. Additional factors, such as desk layout and building system design (e.g., luminaires, speaker system), also contributed significantly to spatial variability in air temperature, lighting, and sound masking exposures, and this variability was reduced in latter experiments by optimizing desk layout and building system design. While ecologically valid experimental conditions are possible with a living lab, a compromise between realism and consistency in participant experience must often be found by, for example, using an atypical desk layout to reduce spatial variability in natural light exposure. Based on the experiences from these three studies, experimental design and environmental monitoring considerations for future office-based living lab experiments are explored.

A Scoping Review of Technological Approaches to Environmental Monitoring

“…The ASHRAE Standard 55 widely measures thermal comfort [4,32,36] and should be done using occupant satisfaction surveys, point-in-time surveys and electronic sensors measuring the thermal environment [58]. ISO 7730 and ASHRAE 55 standardise a predictive mean vote (PMV) steady-state model [59] used for measuring thermal comfort.…”

“…All but one study measured visual comfort using LUX only (Table 2). The exception [36], measured visual comfort using a combination of LUX and a measure of lighting colour, using the Wovyn Color Lux1000. Their approach measured the impact of blue light on sleep but also the effectiveness of window tinting on a room's ambient colour temperature by placing light sensors at desk level and in elevated positions.…”

“…Whilst those standards provide strict limits on noise levels, they do not translate to acoustic comfort. In offices, noises often come from mechanical or electrical equipment, conversations or phone calls from surrounding occupants [36,72] (Figure 2).…”

Impacts of Dynamic LED Lighting on the Well-Being and Experience of Office Occupants

“…It was found that during the study operation these factors were in the normal range for a typical office building [ 92 ]. For more details on the measurement and assessment of these parameters in a living lab, please refer to [ 63 ].…”

Minimising the Deviation between Predicted and Actual Building Performance via Use of Neural Networks and BIM

“…A case study by The Carbon Trust, (2012) indicated that an extra £10/m2 in annual operating energy costs resulted due to the performance gap between predicted and actual performance of the building [21]. The evolving nature of the world paved the way for the introduction of various capacity-extending technology, including automated sensors [22], artificial intelligence (AI) [23], and digital models, including building information modelling (BIM) [24]. The integration of all the latter is the topic of various discussions on the practical and research arenas [25].…”