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This paper aims to demonstrate the optimization of an existing residential building in a tropical climate using indigenous materials as an alternative to conventional building envelopes to achieve thermal comfort and affordable housing.

This study mainly adopted a quantitative research methodology through a comprehensive simulation study on a selected prototype building. The energy plus simulation tool in DesignBuilder was used to predict the average monthly and annual thermal comfort of a typical residential building in the study area. Also, a cost analysis of the final optimization interventions was conducted to estimate the construction cost savings.

The comparative analysis of simulation results for the base-case and optimized models indicates potential advantages in replacing conventional building envelope materials with indigenous materials. The base-case simulation results showed that the annual operative temperature is more than the adaptive thermal comfort set points in tropical climates, by 8.26%. This often leads to interventions using mechanical cooling systems, thus triggering overconsumption of energy and increase in CO₂ emissions. The building envelope materials for floor, walls and roof were replaced with low U-values indigenous materials until considerable results in terms of thermal comfort and overall building construction cost were achieved. The final simulation results showed that using indigenous materials for the ground floor, external walls and roof could substantially reduce the annual operative temperature by 8%, thereby increasing the predicted three months of thermal comfort in the base-case to nine months annually. Likewise, there was a 32.31%, 35.78% and 41.81% reduction in the annual CO₂ emissions, cooling loads and construction costs, respectively.

The knowledge of indigenous materials as an alternative to conventional materials for sustainable buildings is not new. However, most of the available research is focused on achieving affordable housing. There is a dearth of research showing the extent that these indigenous materials can be used to improve indoor thermal comfort in developing countries with tropical climates such as Nigeria.

This research is oriented to the need for new ideas related to the concept of a green campus that respond to climate change. The concept is simulated with a campus area in Indonesia, a country that requires a lot of school planning for human resource development that requires clean, renewable energy and zero emissions in a humid tropical climate.

The research was carried out in a mixed qualitative-quantitative method using field observations and literature studies through an approach to developing a pedagogical pattern of cognitive, affective and psychomotor, relevant theoretical studies and comprehensive analysis of all variables and aspects. Analysis through the parameter matrix of green buildings and green campuses to produce a zero emission and energy efficient campus area concept.

The concept of an integrated campus area model that can holistically save energy optimally and free from emissions and can produce graduates who are aware and have high cognitive, affective and psychomotor competencies toward environmental conservation efforts. Green campus design is not only physical design, but needs to be integrated with green curriculum content.

The limitation of this research is in the scope of architectural and environmental sciences.

The practical implication of this research is a new green campus concept that is environmentally friendly and sustainable in a hot-humid tropical climate.

This research revives the cognitive, affective and psychomotor competencies of human individuals at the highest level to equip the ability to repair and maintain the environment. The research resulted in a refinement of the green campus concept that was integrated into the curriculum.

A holistic and integrated green campus concept between the development of campus area design and human development aspects.

Cracks in the roof parapet wall and damage to the waterproofing membrane are the common defects of roof construction that require frequent maintenance. This paper seeks to review the common defects of roof construction of medium‐rise buildings in sub‐tropical climates.

The research reported was carried out by the survey and analysis of 20 case study buildings. The modes of rooftop parapet wall dislocation are studied and the effects of thermal expansion and end conditions of the parapet wall on the damage to the waterproofing membrane are analysed.

Parapet wall dislocation failure is dependent on whether the ends are hinged or fixed. Failure usually leads to tearing of the waterproofing membrane.

Modification to the roof parapet wall design and to the selection of construction materials is suggested.

The modes of failure and proposed modification will be of interest to designers and those responsible for the maintenance of flat‐roofed buildings in sub‐tropical climates.

A thermosyphon solar water heating system with in‐tank auxiliary electric heater has been simulated according Malaysian hot water consumption profile using TRNSYS simulation program. The optimum value of a parameter is defined as the value which maximized the annual solar fraction of the system. This paper has a good deal of information concerning sizing of common components of thermosyphon solar water heater operated under certain condition (load volume, distribution profile and temperature). The results indicate that collector should be tilted at Ø + (→ 7° 37°) for all collector areas. Vertical storage tank has better performance in tropical climate (The average annual solar fraction for vertical was 88% and for horizontal was 82.9%).

The purpose of this paper is to adduce the most appropriate thermal comfort assessment method for determining human thermal comfort and energy efficient temperature control in office buildings in tropical West Africa.

This paper examines the Adaptive Thermal Comfort Standard, from its research evolution to its contemporary use as an environmental design assessment Standard. It compares the adaptive component of ASHRAE Standard 55 and the European CEN/EN 15251. It begins by reviewing relevant literature and then produces a comparative analysis of the two standards, before suggesting the most appropriate Adaptive Thermal Comfort Standard for use in assessing conditions in tropical climate conditions. The suggested Standard was then used to analyse data collected from the author's pilot research into thermal conditions, in five office buildings situated in the city of Enugu, South Eastern Nigeria.

The paper provides insight as to why the ASHRAE adaptive model is more suitable for thermal comfort assessment of office buildings in the tropical West African climate. This was demonstrated by using the ASHRAE Thermal Comfort Standard to assess comfort conditions from pilot research study data collected on Nigerian office buildings by the author.

The paper compares the adaptive component of ASHRAE Standard 55 with CEN/EN 15251, and their different benefits for use in tropical climates. It suggested the need for further research studies and application of the ASHRAE Adaptive Thermal Comfort Standard in the tropical West African climate.

Waiting for a bus may represent a period of intense exposure to traffic particles in hot and noisy conditions in the street. To lessen the particle load and tackle heat in bus stops a shelter was equipped with an electrostatic precipitator and a three-step adiabatic cooling system capable of dynamically adjust its operation according to actual conditions. This study evaluates the effectiveness of the Airbitat Oasis Smart Bus Stop, as the shelter was called, to provide clean and cool air.

The particle exposure experienced in this innovative shelter was contrasted with that in a conventional shelter located right next to it. Mass concentrations of fine particles and black carbon, and particle number concentration (as a proxy of ultrafine particles) were simultaneously measured in both shelters. Air temperature, relative humidity and noise level were also measured.

The new shelter did not perform as expected. It only slightly reduced the abundance of fine particles (−6.5%), but not of ultrafine particles and black carbon. Similarly, it reduced air temperature (−1 °C), but increased relative humidity (3%). Its operation did not generate additional noise.

The shelter's poor performance was presumably due to design flaws induced by a lack of knowledge on traffic particles and fluid dynamics in urban environments. This is an example where harnessing technology without understanding the problem to solve does not work.

It is uncommon to come across case studies like this one in which the performance and effectiveness of urban infrastructure can be assessed under real-life service settings.

The following editorial aims to highlight the potential impact that efficient facilities management with regards to agricultural ventilation systems could have in hot climates.

Through a review of the literature surrounding different ventilation systems and their benefits and disadvantages on milk production, evidence to support the aims was compiled. Through looking at the direct effects on milk yield and how these values vary across the globe a scope of the potential effect of better facilities management was created.

This paper found that although more expensive to install and power mechanical ventilation provided many benefits to animal welfare and productivity. However, in contrast developing countries were relying upon more traditional methods such as natural ventilation, which have limitations in tropical climates. By using India as a case study the potential benefits of improving productivity on the emissions of green house gases was illustrated.

The findings in this editorial are limited by the quality and amount of literature currently published regarding ventilation methods in many developing nations such as India.

Practically it is a complex process to quantify the processes involved in milk production. Therefore, the data referenced in this editorial is subject to vary across the globe with contrasting farming techniques and livestock breeds.

This paper brings an original view on how better management of ventilation systems; most noticeably within developing nations with hot climates could potential produce large benefits. Through increased productivity within the world's largest milk producers the green house gas emissions from agriculture can be reduced.

The self-cleaning properties of nanostructured titanium dioxide facade coatings are useful in Singapore's tropical climate. However, its potential maintenance issues need to be determined right at the design stage. The purpose of this paper is to highlight the development of the design for maintainability tool which is a multicriteria design decision score sheet that evaluates the maintainability potential of nano-facade coating applications on high-rise façades with concrete and stonemasonry finishes and curtain walls.

Quantitative methods (expert and practitioner surveys) are conducted in this research study. Analytic hierarchy process (AHP) and sensitivity analysis were used to develop a robust Design for Maintainability tool.

Safety measures indicator received the highest weighted score by experts, while the maximizing performance, minimizing risk, minimizing negative environmental impact and minimizing consumption of matter and energy were the top ranking main criteria by both experts and practitioners. The top ranked design for maintainability sub-criteria identified by practitioners and experts were risk management, maintenance considerations, climatic conditions, safety measures, lifecycle cost and maintenance access, sun's path, rainfall intensity, biological growth measures and building age profile.

Most researches on the maintainability of nano-façade coatings uses experimentation to test the durability of nano-façade coatings, while this study focuses on design based empirical data such as establishing and ranking the list of design for maintainability criteria or indicators to minimize future defects and maintenance issues. The design for maintainability tool contributes to the maintainability of nano-façade coatings leading to maximizing its performance while minimizing cost, risks, resource consumption and negative environmental impact.

Señor Ruiz‐Morales emphasized at the outset the diversity of the economy of Spain. Not only was Spain cut off from the rest of the European continent by the Pyrenees, but land communications between one region of Spain and another were greatly handicapped by the mountainous nature of the country. The centres of both industrial and agricultural activity lay along the coastal belt, from Bilbao in the north to Barcelona in the south. In the centre was the meseta, the high plateau, dominated by Madrid. In the case of agriculture it was important to distinguish between the land distribution of the south (on the latifundia system) and the very small holdings (minifundia) of the north. Crop growing was concentrated in the valleys and the semi‐tropical climate of the south enabled Spain to export citrus fruits. Most of Spain's mines had been worked for a long time and were nearly exhausted. The country's deficiency was in two vital sources of power—coal and oil. Hydro‐power was, however, being utilized in the Pyrenees (for the Barcelona industrial region) and where the Douro and the Tagus dropped into Portugal. In the early ‘thirties Spain had a considerable gold reserve, but this had been lost to Russia, for the gold had been sent to that country at the time of the Spanish Civil War. Foreign aid was providing an important incentive to economic progress.

A new instrument added to Sheen Instruments range will be of particular value to painters of all manner of steel structures, specially in Britain and other non‐tropical climates where condensation can be a problem.