sustainability Article Post-Occupancy Evaluation of Indoor Air Quality and Thermal Performance in a Zero Carbon Building Polina Trofimova 1 , Ali Cheshmehzangi 1,2, *, Wu Deng 1 and Craig Hancock 3   Citation: Trofimova, P.; Cheshmehzangi, A.; Deng, W.; Hancock, C. Post-Occupancy Evaluation of Indoor Air Quality and Thermal Performance in a Zero Carbon Building. Sustainability 2021, 13, 667. https://doi.org/10.3390/ su13020667 Received: 11 December 2020 Accepted: 6 January 2021 Published: 12 January 2021 Publisher’s Note: MDPI stays neu- tral with regard to jurisdictional clai- ms in published maps and institutio- nal affiliations. Copyright: © 2021 by the authors. Li- censee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and con- ditions of the Creative Commons At- tribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). 1 Department of Architecture and Built Environment, University of Nottingham Ningbo China, Ningbo 315100, China; Polina.Trofimova@nottingham.edu.cn (P.T.); Wu.Deng@nottingham.edu.cn (W.D.) 2 Network for Education and Research on Peace and Sustainability (NERPS), Hiroshima University, Hiroshima 739-8530, Japan 3 School of Architecture, Building and Civil Engineering, Loughborough University, Loughborough LE11 3TU, UK; c.m.hancock@lboro.ac.uk * Correspondence: Ali.Cheshmehzangi@nottingham.edu.cn Abstract: Maintaining a comfortable indoor environment throughout the year makes up the main part of energy consumption caused by people’s use of buildings. In recent years, China has started to integrate sustainable technologies into green building design and construction. However, some post- occupancy reports on certified buildings revealed that such integration has been perceived to pri- oritize energy savings over comfort. This paper aims to investigate the ability of the first Chinese zero carbon building to maintain comfortable and healthy indoor conditions in the summer season. The research implements a combination of occupant survey and on-site measurements to evaluate the occupants’ perception of the indoor environment quality (IEQ) and benchmark the measure- ments against relevant standards. The results from this study show that the mean summer indoor temperature was 0.9 ◦ C above the standard limit, while on average, occupants gave a positive score to the indoor thermal environment. High contentment with the building acoustics was reported by users and supported by sensors measurements meeting the standard values. The illuminance levels were mainly maintained high with the exception of the light in one of the studied zones. Analyzing the data on occupants experiencing sick building syndromes revealed that 45.8% of respondents experienced at least one of the symptoms. Keywords: IEQ; sustainable building; indoor environment; health 1. Introduction Buildings account for almost a third of total world energy consumption [1] and thus are the major source of carbon dioxide gas emissions. Sustaining a comfortable indoor environment with outside temperatures varying throughout the year makes up the main part of energy consumption caused by people’s use of buildings [2]. To minimize energy usage in buildings, the Paris Agreement [3] sets the goal for achieving energy efficiency, sustainability, and carbon neutrality for the architecture, engineering, and construction (AEC) industry as well as all other industries [4–6]. Achieving this aim requires common application of sustainable strategies for green building design and construction [7]. The World Green Building Council defines green buildings as an attempt to increase all the positive and decrease all the negative impacts of buildings on the natural environ- ment [8]. They extensively practice energy and water-saving techniques, apply on-site renewable energy generation, and use sustainable and non-toxic materials that can later be reused or recycled [8]. An even more advanced version of green buildings is known as zero energy buildings (ZEB), which can be defined differently based on the boundary and metrics used for the evaluation. These definitions can be found in works done by Kurnitski et al. [9], Peterson et al. [10], and Torcellini et al. [11]. Zero carbon buildings (ZCB) belong to this group of highly energy-efficient buildings and they have a definition Sustainability 2021, 13, 667. https://doi.org/10.3390/su13020667 https://www.mdpi.com/journal/sustainability