Balancing comfort expectations and greenhouse gas emissions, thermal comfort in office buildings in a changing climate

According to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), the construction sector has the greatest potential for climate change mitigation. This work investigates the potential for climate change mitigation in naturally ventilated and mixed mode office buildings, by evaluating the range of influence of building design and occupants on greenhouse gas emissions as well as thermal and visual comfort.

Thermal comfort is evaluated according to the EN 15251 adaptive thermal comfort model, visual comfort is based on daylight autonomy and view. Parametric studies have been conducted based on building simulation for the climate of Athens, Greece. Input data are based on a literature review, and on results from a field study conducted among office occupants and architects in Athens.

The results show that the influence of occupants on greenhouse gas emissions is larger than the influence of building design. Energy saving office equipment, as well as active use of building controls for shading and lighting by occupants are crucial parameters regarding the reduction of CO2 emissions. In mixed mode buildings, the coefficient of performance of the cooling system is an important parameter as well. Regarding thermal and visual comfort, the influence of building design is predominant. A green building, well protected against heat from the sun and able to balance solar and internal heat gains, provides higher comfort levels and is less affected by the influence of occupants. In mixed mode buildings, building design is the predominant influence on the magnitude of cooling loads. A hot summer including heat waves can significantly reduce thermal comfort and increase the resulting greenhouse gas emissions. Green buildings are least affected by these influences.

The EN 15251 adaptive thermal comfort model provides a thermal comfort evaluation method valid throughout Europe. However, for the Mediterranean climate of Athens, Greece, most of the configurations investigated within this study do not meet the requirements according to this model. EN 15251 refers to an adaptive thermal comfort model for naturally ventilated and to a static model for mechanically ventilated buildings. For mixed mode buildings, the static model is recommended, but literature indicates that occupants in those buildings might be more tolerant towards higher temperatures. The hypothetical application of the EN 15251 adaptive thermal comfort model in mixed mode offices, as investigated in this study, shows potential for greenhouse gas emission savings. However, this influence is small compared to that of building design and occupants. Conclusions are drawn regarding the categorisation and exceeding criteria according to EN 15251 adaptive thermal comfort model for offices in a Mediterranean climate.

The results of this work show, that not only green buildings, but also green occupants can significantly contribute to the mitigation of the climate change. Mechanisms of the real estate market as well as the lifestyle of occupants are important influences in this context. Sustainability therefore refers to finding the right balance between occupant’s comfort expectations and resulting greenhouse gas emissions for a specific building, rather than optimisation of single parameters

Balancing buildings and occupants - a holistic approach to thermal comfort and greenhouse gas emissions in mixed mode offices

This paper describes a holistic approach to comfort and greenhouse gas emissions in mixed mode offices. It is based on parametric studies for a typical cellular office in the Mediterranean climate of Athens, Greece, using building simulation.

Considered parameters are the influence of different building design, varying occupant behaviour and internal heat loads, as well as of an exceptionally hot summer. Additionally, the performance of a cooling strategy following the comfort limits according to the EN 15251 adaptive model is compared with the common fixed cooling set point 22°C.

The performance of mixed mode offices is evaluated regarding thermal comfort, daylight autonomy and related greenhouse gas emissions. Results indicate strategies to improve sustainability in mixed mode offices in Athens, by balancing the influencing parameters.

Better definitions, better buildings?

Because of the magnitude of their impact on the environment, the way we design, build and operate our buildings must change. So-called ‘sustainable’ buildings are now appearing in our cities. However, the term ‘sustainable’ is now so widely used that it has lost all meaning. Other equally ill-defined descriptions are also being used of the new generation of buildings appearing in the built environment. These terms, including ‘environmentally friendly’, ‘low energy’ and ‘green’. This paper argues that a lack of clarity over meaning can foster illusions, reflect careless thinking and/or provide cover for a business-as-usual agenda. In universities, courses for today’s architecture and construction management students are being redesigned to include ‘sustainability’. However, a review of subject guides from Schools of Architecture in Australian universities indicates that ‘sustainability’ is also being used misleadingly. While there is merit in both of the professional accreditation systems for buildings in Australia, there is certainly room for improvement. One scheme reinforces illusions by rewarding features that should merely be regarded as good building design. The ‘sustainability’ objectives of the other scheme have narrowed significantly from the original intent. The authors conclude that the critical thinking of our students will be sharpened by defining sustainability correctly and that meaningless descriptors of buildings must be challenged.

Height and construction costs of residential high-rise buildings in Shanghai

A widely recognized theme of construction economics suggests that the cost of construction per square meter increases as building height rises. However, over a number of years, research conducted regarding the height and cost issue has established a classic relationship between the two factors which can be represented by a U-shaped curve. This paper describes the study of the height-cost relationship of high-rise residential buildings in Shanghai in terms of the total construction cost and elemental costs while considering the context and commonality of buildings. This research was developed as an extension of the previous work, which examined data for buildings in Hong Kong. Initial findings indicate that the curves illustrating the relationships between height and cost of residential buildings in Shanghai and Hong Kong exhibit different profiles. The dissimilarities indicate that different sets of criteria should be applied in the judgment of height that affects cost in different locations. In terms of elemental costs, the findings suggest that there are differences in the way these costs react to changes in the building height.

Multi-market industrial organizational economic models for the internationalization process by small and medium enterprise construction design service firms

Small and medium enterprises (SMEs) are critical to strategic initiatives in an economy; however, their contribution to foreign trade is not as significant. SMEs are one of the principal driving forces in economic development. One of the greatest challenges is the internationalization process for longevity rather than seeing the process as initial market entry. The internationalization process research has typically involved four key constructs: market selection, decision to enter, entry modes and factors affecting entry modes. Past research has focused on large manufacturing firms. The export of architectural, engineering and construction (AEC) firms has undergone growth, yet there is still significant opportunity for further growth. The majority of AEC firms are SMEs. Notwithstanding assistance provided through international trade missions, organized export firm support networks and information packages by a burgeoning number of government agencies, there are still perceived barriers to market entry and long-term economic sustainability for SMEs. There are a number of problems faced by SMEs acting in foreign trade. This investigation explores the successful initial internationalization process constructs and identifies unique project-oriented sector characteristics. The study identified similarities and differences between two firms that have been exporting to various localities, including Eastern Europe, Africa, Middle East, UK, Asia and South America, for more than two decades. The similarities and differences were identified within eight major constructs: purpose, firm type, market image and design philosophy, entry mode strategy, institutional arrangement, factors affecting mode of entry, market selection and firm strategy in relation to project selection. The primary reasons for internationalization were associated with the firms' motivations related to growth and financial viability. This article discusses the various internationalization processes and strategies intrinsic to each case study and establishes a detailed set of empirical observations from which to develop further a grounded theoretical model of reflexive capability for the internationalization process. This study contributes to the body of knowledge around the SME AEC design service firm's internationalization process, as a dynamic, evolving and continuously adaptable construct for project-based sectors.

The business case for sustainable office buildings

The market for sustainable buildings has rapidly gained momentum in the design and construction phases, however it appears that development and investment in these buildings by the private sector is limited. This is further complicated by the limited information available confirming the financial viability of sustainable buildings, with relatively little research conducted into the relationship between sustainability and the market value of commercial buildings. Currently the demand for sustainable buildings in Australia and New Zealand is being encouraged through government legislation and policy, where investment by the private sector has been relatively slow to develop due to the lack of evidential proof of the economic viability of sustainable buildings. Clearly if the progress and uptake of sustainable buildings is to develop within the property market, it is essential that the relationship between market value and sustainability should be understood in order to fully inform the investment industry.

E-book devices and m-commerce : what might be the impact on organizational learning?

E-book devices are changing current organizational practices by providing a source of e-learning, in which organizations and their employees can more easily access information about current business developments that impact on their existing practices. E-book devices (also referred to as e-book readers or e-readers) use electronic ink technology to display written words from books, newspapers, magazines and other documentation. They are portable devices that are the size of a paperback book and are a new technology that has only been mass-marketed to the general population in the past year. Most importantly for an organization is that e-books could transform and will certainly influence their current technology practices and how people communicate and perform their job tasks.