With transition to knowledge-based society, importance of knowledge creation and communication were pointed out and a lot of studies were conducted. This study is intended to clarify the influence of indoor built environment on “communication effort” in conference room and meeting space. When we think about relationship between communication effort and indoor built environment, it must be needed to consider how environment is captured in personal construct system, and how it is evaluated on this concept. Then, interview, which aimed to understand personal construct about communication effort, and experiment about subjective evaluation on different acoustic environment were conducted in conference room.
Sixteen office workers were interviewed with evaluation grid method. By using the photographic images of conference room or space from their own office as evaluation elements, they were asked their preference rankings of elements with considering communication effort and reasons of rankings about top two preferred elements. Evaluation words, obtained from the interview, could be classified into three categories; their sensation for the meeting environment (E), their mental conditions in the meeting environment (M) and actions or purposes in the meeting (A). Putting participant's answers all together, peaks of each category items in number appeared in the order of E, M, A on laddering steps. In addition, by replacing evaluation words with E, M and A, each participant's answer formed EMA chain. Hence, personal construct system in meeting could be described with E, M and A, and EMA chain was the most typical pattern of answers.
Next, we conducted a psychological experiment to clarify the influence of acoustic environment on communication effort in experimental conference room with sixteen participants. Evaluation items were selected from each category words of E, M and A considering experimental condition. Acoustic condition, absorption coefficient and background noise level, was changed with minimum change of visual condition. The results of subjective rating were affected by acoustic condition, in terms of not only auditory sense but also the sense relating to both auditory and visual sensation, mental conditions and actions. Three factors were derived by factor analysis. Factor 1 and 3 had large factor loads of E and A, and factor 2 was mainly composed of M category items.
Those three factors, which indicate human evaluation framework on acoustic environment in meeting, have two aspects. One is functional aspect relating to sound transmission and meeting efficiency, the other is feeling aspect like comfortableness in meeting. In other words, feeling aspect is thought to relate on the emotion, affecting people's attitude when they interpret another person's speech and reply answer. It should be possible to design totally good meeting environment considering both functional aspect and feeling aspect. Acoustic condition affected evaluation items of M category in the psychological experiment, even though those had weak relation with acoustic environment in the result of interview. For making better communication effort, it must be important to design both visual and acoustic environment in consideration of those influences which people does not recognize.
