The aim of this thesis is to investigate to what extent regulated office clothing affects the perception and adaptation of office workers to the thermal conditions surrounding their work environments, focusing on the city of Enugu in South Eastern Nigeria which has hot humid climatic conditions. Clothing, regarded as a second skin, allows us to adapt or adjust to the thermal conditions in our immediate surrounding environment. It also affects our perception of the thermal environment. In some offices however employees are expected to wear regulated clothing or uniforms, during the working day; for various corporate identity reasons. Field studies were undertaken in office spaces in Enugu involving the behavioural and environmental analysis of thermal comfort conditions in six typical case study office spaces, at the Federal Radio Corporation of Nigeria (FRCN) and Federal Road Safety Corps (FRSC). The thesis adopted a mixed‐mode methodological process; combining a quantitative and qualitative approach to data collection and analysis. The field research analysis found that all office spaces analysed were in compliance with the adaptive thermal comfort component of the ASHRAE Standard 55‐2013. The results however did not comply with the adaptive thermal comfort of CEN/EN 15251‐2007. The thermal sensation component of the results suggests a neutral temperature of 28.80C, with 80% thermal satisfaction, in a comfort range of between 25.40C and 32.20C. The thermal comfort vote indicates that approximately 85% of office workers with flexible clothing policy were comfortable at that comfort range, whilst only 55% of workers who had to adhere to a strict uniform policy voted that they were comfortable. The key research findings were: Firstly, the field observations and semi-structured interviews undertaken indicated that the strict uniform policy of FRSC office workers contributed substantially to the limited adaptation of staff to their workspace thermal conditions. Also, of all the thermal variables recorded during the field survey, clothing insulation had the strongest correlations to the thermal sensation of participants in the survey compared to indoor operative temperature, outdoor air temperature, relative humidity or metabolic rate. Furthermore, it is possible for workers in naturally ventilated office buildings in the hot humid climate zone of Enugu to achieve thermal comfort in higher temperature conditions through clothing adaptation.

It is widely recognised that one's ability of adaptation is remarkable and thermal comfort is significantly related to such adaptations. This study proposes an alternative method of predicting adaptive thermal comfort based on the availability of adaptations, in particular behavioural adaptations, which needs quantifications of individual adaptation processes and of interactions between them. The fundamental argument of this method is that exercising an adaptive behaviour leads to an increase in comfort temperature, which is termed adaptive increment in this study. Apart from adaptive increments, this method also determines a baseline thermal comfort temperature (the thermal comfort temperature without adaptations) and a correction factor that considers the factors affecting adaptive behaviours, based on which, the highest operative temperature at which people may still feel thermally comfortable. This may be applied in mixed mode (MM) buildings to achieve a higher air-conditioning (AC) setpoint which may lead to a significant reduction in cooling energy. This method is believed to be flexible in dealing with different environments with various levels of adaptations and likely to be advantageous over the steady-state and adaptive models in predicting thermal comfort temperature of an environment with abundant adaptive opportunities. This study also evaluates ways of promoting the use of adaptive opportunities. It explores how adaptive thermal comfort theories may be used for behaviour modelling and in turn be applied to enhance the energy performances and comfort levels of real buildings. To improve the feasibility of this method key effective adaptive behaviours are studied in detail through lab experiments and field studies. The lab experiment has found the adaptive increment of taking cold water to be 1.5°C which is more significant than the previous literature suggests. When all the studied adaptive behaviours are exercised, the overall adaptive increment is as high as 4.7°C. However, the research has identified some issues associated with the adaptive opportunities studied. These include the existence of constraints on the use of adaptive behaviours, the low availability of some effective adaptive opportunities, the low operation frequency of desk fans and the misuse of windows and AC systems. Despite this, the availability of more adaptive opportunities has been verified to be capable of increasing the highest operative temperature at which people may still feel thermally comfortable: the lab experiment shows that over 80% of the participants can still find it thermally comfortable at an operative temperature of 30°C on the condition that adequate adaptive opportunities are provided; the field study shows that the thermal comfort temperature of occupants increases by at least 1°C when desk fans and cool mats are available. Based on these analyses, it proposes an MM system which encourages occupants to exercise adaptive opportunities and improves both comfort levels and energy efficiency. Building performance simulation results show that the proposed MM system is effective in reducing the reliance on AC systems and promotes effective uses of windows and AC systems. By applying the MM system and the associated passive energy-saving strategies, an office can cut cooling energy by about 90% and the peak cooling load by over 80% during transitional seasons.

No description available.