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Amidst the recent development in the usage of curtain walls for office buildings, high utilization of energy and poor thermal comfort issues have become paramount. This paper assesses thermal comfort in multi storey (naturally and mechanically ventilated) office buildings in Accra, the Capital city of Ghana using

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Purpose The ever-increasing demand and consumption of energy and the effects of global warming with its long-term comrade, climate change, is obvious today than ever before. In today’s world, naturally-ventilated buildings hardly provide the satisfaction that occupants need and wish for. It’s on this backdrop that the study aims to investigate how responsive buildings on the Kwame Nkrumah University of Science and Technology, Kumasi, Ghana campus are to its warm humid climate and assess students thermal comfort levels. Design/methodology/approach Quantitative approach was adopted for the study. Empirical investigation was carried out using the survey approach. In total, 14 buildings (offices, classrooms and halls of residences) were assessed using the Mahoney Tables. Again, subjective thermal perceptions of occupants in the halls of residences was sought. A total of 214 valid questionnaires were used for the analysis. Findings Adaptive principles like the Mahoney Tables are not followed in recent years. Even where these principles have been followed, indoor spaces were still found to be uncomfortable. In total, 58 per cent of the occupants in all the three halls of residence voted in the comfort band: an indication unacceptable sensations. Warm sensation votes (44 per cent) was more than cool sensation votes (29 per cent). In warm sensation, 39 per cent of the subjects preferred cooler environment. The occupants felt that opening windows and the use of fans could keep them comfortable. Moreover, 48 per cent of the subjects voted that their fans and windows were effective. Originality/value The papers contribution to the body of knowledge is the provision of empirical evidence in the field of adaptive designs and thermal comfort. There is a strong indication from the results that human activities in terms of blatant disregard for laid down design principles coupled with the worsening situation of global warming is making interior spaces ever uncomfortable.

PurposeGiven the climatic context and economic challenge of Ghana in its developmental strides, energy use of office buildings continues to be a task on the economy. Therefore, the study was about finding measures that could reduce cooling loads in 10 office buildings. The paper presents the outcome of a long-term study of the thermal conditions in a selected number of office buildings in Accra and Kumasi, Ghana.Design/methodology/approachThrough long-term monitoring of environmental data, the buildings were consequently modelled in a simulation application. Thereafter, a validation of the simulation models (using regression coefficients, r2 of 0.53–0.90) was undertaken towards finding measures to reduce cooling loads.FindingsThe results showed various potentials of efficient lighting, thermal mass, night ventilation, insulation to attic floors, efficient glazing, blind deployments, etc. in reducing cooling loads in the range of 2–17.5%. By combining the potential measures to study their synergistic effects on the loads, 35, 39 and 38% improvements were achieved for the low-rise, multi-storey and fully glazed office buildings.Originality/valueThese potential measures ought to be incorporated in the design, specification, construction and operation of Ghanaian office buildings to reduce the burden on the economy and the environment. Now more than ever, there is the need for climatic regions to come up with empirical data that could help relieve the world's economies from the post-pandemic stress.

PurposeAs the global population keeps increasing with its associated urbanisation and climate change issues being experienced in various degrees worldwide, there is the need to find mitigating measures to improve thermal conditions within spaces. The study aimed to evaluate green roofs to determine whether they could provide thermal comfort within residential buildings.Design/methodology/approachForty-two-year weather data were retrieved from the Kumasi weather station to establish the pattern of the climatic variables. Furthermore, an experiment was conducted by constructing test cells to determine the potential of vegetation/green roofs on temperature development within spaces. This approach led to a simulation-based exploration of the thermal performance of the test cells to probe variables that could lead to the reduction in temperature after the models in the software (design-builder) had been validated.FindingsThe results on the 42 years (1976–2018) weather data showed a significant (p = 0.05) mean temperature increment of 2.0 °C. The constructed test cell with Setcreasea purpurea (Purple Heart) vegetation showed an annual mean temperature reduction of 0.4 °C (p = 0.05). In addition, the exploration using the simulation application showed combinations of various soil depth (70–500 mm) and leaf area indices (leaf area index of 2–5) having a potential to lower indoor temperature by 1.5 °C and its associated reduction in energy use. The option of green roofs as a valuable alternative to conventional roofs, given their potential in mitigating climate change, must be encouraged. A survey of occupants in six selected neighbourhoods in Kumasi showed varying subjective perceptions of several green issues (24–98%) and increases in temperature values because of the loss of greenery in the city.Originality/valueEmpirical data that point to the significant reduction of indoor temperature values and a subsequent reduction in energy use have been unearthed. Therefore, built environment professionals together with city authorities could invest in these sustainable measures to help humanity.

The role that natural lighting plays in buildings cannot be underestimated. Natural light is integrated into buildings because of its potential economic benefit and the effect on the occupants' psychological and physiological well-being. This study concentrates on Ayeduase, a suburb of Kumasi, Ghana, where students live in hostels with poor architectural design. Therefore, the primary aim of this study is to investigate the health and visual comfort of students living in Ayeduase, by creating awareness of the positive effects of natural light on humans. Questionnaires and interviews, as well as empirical measuring of daylight levels in the spaces of selected hostels were used. Analysed data revealed that the level of illuminance in the hostels is considerably poor and this resulted in students using artificial lighting throughout the day. Nevertheless, the negative effect of this situation can be prevented from occurring in further developments in Ayeduase (and Ghana as a whole), by educating designers on the benefits of using natural lighting in buildings and by enforcing laws that will ensure that buildings have maximum openings that allow enough daylight into the interior spaces. These measures will help reduce utility costs, improve the well-being of building occupants and increase the performance of students.

ABSTRACT:Building designers are advised to use sustainable design measures in order to make spaces comfortable, before applying mechanical systems. An important aspect of sustainable design is orientation, specifically the rule to orient buildings to the north and south. However, in an attempt to employ this sustainable principle, various cultures resort to different myths as means of justification. The paper presents historical and modern views and theories on orientation of building forms, spatial components, and the surrounding myths worldwide. The results showed that even though the recommended orientation is mostly the north-south, the myths around this measure are sometimes rooted in the culture of places. For instance, the Chinese, many of whom practice the Feng Shui theory, support design recommendations that follow the flow and balance of positive (yang) and negative (yin) energies. Furthermore, room heights between 3 and 3.5 metres, centrally placed dining spaces and main entrance to buildings in the South are common principles worldwide.