Barbara Simons

This study analyses the visual comfort of classroom spaces of Public Basic Schools (PBSs) in Ghana based on window-to-wall ratios through a simulation approach. Three fenestration types were identified as being the most predominantly used openings in PBSs and therefore formed a focal part of the study. Eight scenarios based on the features of the classrooms were used in the simulations. It was found that an 8% WWR for a classroom was inadequate and would require supplementary lighting to be provided, irrespective of the fenestration type. This WWR would afford pupils sitting only at the edge of windows to be visually comfortable. In a scenario where a classroom has casement fenestration with 15% WWR and has verandahs on both side-lit walls with a North-South orientation, adequate daylight illuminance (≥ 200lux to<750lux) could be achieved for 63.4% to 65.1% of classroom space. Supplementary lighting would be required for the “middle front”, and “middle back” of the classroom in both climatic zones. Comparatively, if the verandahs are East-West oriented, a much higher percentage of classroom area would receive adequate daylighting (66.4% to 73.4%) and would require supplementary lighting for occupants only in the “middle” and “middle back” areas of the classroom. This study opens up a new area that has been largely overlooked in Ghana.

Net zero energy buildings (NZEBs) play a crucial role in mitigating the environmental impact of the construction industry. However, this concept in Ghana is still in the infancy stage, and the level of embracement in the construction industry is uncertain which further poses challenges to its adoption. This can be attributed to the lack of awareness of NZEB among construction professionals. Hence, understanding the awareness among construction professionals is essential for promoting sustainable building practices and reducing the carbon footprint of buildings. Therefore, this study investigates the level of awareness of NZEBs among construction professionals in the Ghanaian construction industry (GCI). The study adopted a quantitative research method where questionnaire survey was used to obtain data from sixty-six (66) construction professionals in the GCI through snowball sampling technique. The collected data were analysed using frequencies, mean scores, one-sample t-test and cross-tabulation. The study revealed that thirty (30) construction professionals out of the sixty-six (66) had a moderate level of awareness of NZEBs, and 14 professionals had a low level of awareness. Thirteen had a high level of awareness. Three of the profesionals were extremely unaware, while six had a very high level of awareness. The study’s findings highlight the need to create awareness of NZEBs and their practices among construction professionals and employees in Ghana. NZEB is an under-explored area in the Ghanaian context and therefore, this study uniquely highlights the nascent awareness of NZEBs among Ghanaian construction professionals, unlike previous studies in more developed contexts. It underscores the critical need for targeted awareness programs essential for reducing the carbon footprint and advancing the adoption of NZEBs in the GCI.

Purpose: Climate change and global warming are two major ecological concerns. The construction industry has instituted measures such as green construction in response to these concerns. This study seeks to assess the views of architects on the uptake of innovative green construction (IGC) in Ghana.Design/methodology/approach: This study applies the theory of planned behaviour (TPB) to investigate the factors influencing the decision to adopt IGC. A structured questionnaire was issued to architects who have been involved in the design and/or construction of green buildings in Ghana. The dataset was obtained from 61 architects and Partial Least Square was used to analyse the data.Findings: The results show that two TPB factors; attitude and perceived behavioural control are significant determinants of architects’ intention to adopt IGC. Interestingly, behavioural intention did not have an influence on the actual behaviour of IGC adoption. However, perceived behavioural control had a significant impact on the actual adoption of IGC.Practical implications: Contextually, the findings of the study will contribute to policy development and marketing of various green innovation within the Ghanaian construction milieu. Practically, the study will help encourage stakeholders to build the right capacity and competence towards the uptake of IGC.Originality/value: The originality of the paper is based on the theoretical framework underpinning the study and the target respondents as the unit of analysis in assessing the full uptake of IGC in Ghana. The utility of the model evinces the role behavioural changes play in ecological development.

This paper presents the outcome of a long-term study of the thermal conditions in nine office buildings in Accra and Kumasi, Ghana. As part of the aim, the authors sought to evaluate the prevailing thermal conditions in the office buildings and to find measures of reducing overheating tendencies via comfort charts and a simulation approach. The outcome of the study suggests high thermal discomfort feeling in the office buildings because the environmental parameters of temperature and relative humidity values plotted on the various comfort charts illustrated uncomfortable conditions. However, air velocities of 0.5, 1.0, and 1.5 m/s could help to increase the percentage of time (POT) in which the indoor spaces are comfortable within a range of 28% and 98% across the various buildings. Mean overheating temperature values ranged from 1.2 to 5.6 K above the neutral temperature across all buildings. This was associated with a high number of predicted percentages of dissatisfied occupants (24%–65%). In addition to this, American Society of Heating, Refrigerating and Air-Conditioning Engineers’s (ASHRAE) reference temperature for summer comfort, that is, 26°C led to a mean overheating temperature of 0.7–5.6 K in the multistory (MS) structures. Given the potential of improved design options in combination with various air change rates (ACHs) in reducing overheating tendencies, predicted mean votes (PMVs) could be reduced from a mean of 2.7 (hot) to 1.6 (slightly warm) across all buildings. There is a strong indication of the inability of Ghanaian office buildings to fully operate in passive mode from the results. Furthermore, the survey revealed that although building occupants voted air quality and thermal comfort as the most important parameters, they also complained about the inaccessibility of building systems (35%). On the thermal sensation scale, occupants indicated a wild range of conditions with a majority (more than 60%) from cool through warm. Efforts to observe time slots where reliance on natural ventilation would be appropriate through scientific monitoring and performance documentation are being studied. The anticipated ecological and economic benefit to Ghana would be positive amidst the current global challenges.

Purpose: As 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/approach: Forty-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.Findings: The 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/value: Empirical 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.

Given 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. Through 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. The 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. These 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.

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.

Although proper safety management in construction is of prime importance, evidence from literature suggests that many developing countries do not consider safety adequately. This article examines the factors that influence the performance of safety management programmes in the Ghanaian Construction Industry. The objectives set to achieve this aim include identifying the safety elements incorporated in the safety programmes of construction firms, and determining the factors that negatively influence the performance of such elements. For objectivity, a quantitative survey was conducted among safety managers of 60 D1 building construction firms located in the Kumasi and Greater Accra regions of Ghana. The questionnaire was structured into three parts, which sought the respondents’ profile, identified the safety elements incorporated in the firms’ safety programmes, and identified the factors that negatively influence the performance of the safety elements. Following a detailed literature review, the respondents were asked to rate 13 elements and 17 factors on a Likert scale. Data was analysed using the Statistical Package for Social Sciences (SPSS) Version 22. In addition to determining the reliability of the various constructs, the MSs, modes and standard deviations were obtained. The findings revealed that all of the 13 elements were incorporated in the firms’ safety programmes. The key elements identified include ‘providing safety managers on site’; ‘providing written and comprehensive safety and health plans’; ‘introducing project-specific training and regular safety meetings’; ‘providing safety and health orientation training’, and ‘involving employees in safety and evaluation’. The findings further revealed that 16 of the 17 factors negatively influence the performance of the firms’ safety programmes. The identified factors were, among others, ‘insufficient communication of safety programmes’; ‘lack of workers’ self-protection and awareness’; ‘contractors ignoring safety, due to the time pressures of the project schedule’; ‘poor personal attitudes towards safety’, and ‘ineffective laws and lack of enforcement’. Findings from this study should be useful to construction practitioners seeking to improve the safety records of their firms.