Virtual Reality as a tool for evaluating user acceptance of view clarity through ETFE double-skin façades

Flor, Jan-F.; Aburas, Marina; Abd-Alhamid, Fedaa; Wu, Yupeng

Abstract

Equipping building envelopes with an additional layer is an effective measure for improving the overall thermal and daylighting performance and reducing the energy consumption of buildings. This study investigated the user acceptance of energy-saving retrofitting measures in office buildings, reporting on the view perception and emotional response towards ETFE double-skin façades (DSF). Virtual Reality (VR) and physics-based imaging techniques were used to evaluate the user experience of a window view in an office space equipped with a pneumatic ETFE cushion as a second building skin. A 1.2m x 1.2m mock-up was installed externally on the building emulating the DSF. Three DSF scenarios with different ETFE cushions, including a clear, fritted and switchable sample, were evaluated and compared to the original single-skin façade with double-glazed windows. The physical and luminous conditions of an office space were replicated in a virtual environment with a validated physically-based imaging technique and presented to a group of volunteers (N=22) using a virtual reality headset. While immersed in the virtual environment, participants carried out simple visual tasks and responded to a questionnaire enquiring into their view perception and emotional states. The results revealed a preference for view clarity of clear ETFE in double- skin façades (Mdn = 5) and less satisfaction for fritted (Mdn = 4) and switchable foil cushions (Mdn = 1.75), yet double glazing was preferred in all measured parameters (Mdn = 6). Statistical significance was found for fritted in comparison to switchable ETFE in terms of spatial pleasure and control. The highest ratings were given to clear glazing across all investigated parameters of view perception and emotional response. The lowest ranking in all questions was given to the sample with the switchable ETFE cushion. The study concluded that view clarity is a major aspect for the user acceptance of ETFE double-skin façades. Overall this study provides a better understanding of the visual and emotional implications of viewing through ETFE foil and contributes to forming criteria for the design of next-generation ETFE building envelopes.

Citation

Flor, J.-F., Aburas, M., Abd-Alhamid, F., & Wu, Y. (2021). Virtual Reality as a tool for evaluating user acceptance of view clarity through ETFE double-skin façades. Energy and Buildings, 231, Article 110554. https://doi.org/10.1016/j.enbuild.2020.110554

• Journal Article Type: Article
• Acceptance Date: Oct 10, 2020
• Online Publication Date: Oct 15, 2020
• Publication Date: Jan 15, 2021
• Deposit Date: Oct 16, 2020
• Publicly Available Date: Oct 16, 2020
• Journal: Energy and Buildings
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 231
• Article Number: 110554
• DOI: https://doi.org/10.1016/j.enbuild.2020.110554
• Keywords: View Perception; Virtual Reality; ETFE; Double-skin Façades
• Public URL: https://nottingham-repository.worktribe.com/output/4967374
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S037877882032925X
• Additional Information: This article is maintained by: Elsevier; Article Title: Virtual reality as a tool for evaluating user acceptance of view clarity through ETFE double-skin façades; Journal Title: Energy and Buildings; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.enbuild.2020.110554; Content Type: article; Copyright: © 2020 The Authors. Published by Elsevier B.V.