Analysing stakeholder-associated risks in green buildings : a social network analysis method

In the research of risk associated with developing energy and water efficient green buildings, previous studies had mainly focused on "what the risks are and how the risks may impact on project objectives", which were from an inward looking self-perspective and treated the risks in isolation from one another. While intensive research efforts have been dedicated to risk identification, assessment, classification, prioritisation and mitigation, a research gap exists, that is previous studies had ignored the fact that most risks are interrelated and associated with internal or external project stakeholders. To remedy the gap, this current research developed and presented a SNA (Social Network Analysis) based stakeholder-associated risk analysis method to assess risks in green buildings and the interactions between the risks. A case study has been conducted to demonstrate and validate this method. This research contributes to the development of a new theory to model the interdependent and interactive relationships of risks by using SNA as a methodology. This research should broaden project managers' awareness of the influential risks in green building and enhance their ability to perceive, understand, assess, and mitigate the risks in an effective and efficient way, thereby achieving higher performance in strategic risk management and stakeholder communication in green building development.

Carbon dioxide levels and ventilation strategies in 'green' office buildings

Energy efficient office buildings are intended to provide a comfortable and healthy environment for their occupants as well as reducing the energy consumption of the building. They are often designed as "showcase" buildings illustrating the potential for savings through some innovative design technology. But do such buildings actually deliver the desired energy savings and satisfactory comfort conditions for occupants? Measurements of a "green" University campus building in Victoria, Australia, designed with an innovative fabric energy storage system, demonstrate that the ventilation system is not providing acceptable indoor air quality conditions. The design strategies used to reduce energy consumption have had negative consequences on the air quality of the building. Insufficient fresh air is being drawn into the building leading to an excessive build up of carbon dioxide. It is recommended that monitoring systems need to use a wider range of measurements than temperature alone to guarantee good quality indoor air and working conditions and that commissioning of buildings should include adequate monitoring of the operational performance of the building. Designers need to be made aware of the potential consequences of their decisions when attempting innovative energy-efficient designs.

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

The contribution of Building Information Modelling (BIM) to Green Building Design and Assessment in Abu Dhabi "ESTIDAMA"

Estidama is a mandatory Green Building code in Abu Dhabi by which the compliance of building design is being assessed. This paper examines the current design and assessment approaches for Green Buildings to identify the reasons that lead to delay defects and it investigates a new approach for improvement. The available literature provides a realistic understanding to the problems and shows the road to some potential solutions. The identified problems were mainly attributed to the manual assessment with too much human interference. The piled documents with limited resources left the assessment system too slow to handle the whole projects within the greater Abu Dhabi engendering high risk of the commitment to review mistakes. Therefore, this paper investigates the potentiality of automating several stages via the use of Building Information Modeling (BIM) into the assessment process. Different experienced participants from all aspects within the construction industry were interviewed to contribute to the research. Also, a close question questionnaire was distributed to examine the current practice in Abu Dhabi to compare it with the initial findings. The findings point out significant requirements to adopt BIM in the assessment process, such as the availability of proper contracts form to shape the relationship between BIM parties and the readiness of the current system. Hence, the authors suggest a new model that integrates BIM capabilities within the system to accelerate the process and reduce human involvement.

International comparison of sustainable rating tools

This paper undertakes an international comparison of global sustainability tools and examines their characteristics and differences. Most importantly, it focuses on which tools from different countries can be directly compared with each other (i.e., is a five-star building with one rating system directly comparable with a four-star rating of another rating system?). The results are designed to provide some clarification of the assessment tools for sustainable buildings, which in turn will assist investors, developers, tenants, and government bodies in making
informed decisions about green buildings. In addition, it is envisaged that removing some of the uncertainty associated with sustainable buildings will increase transparency for stakeholders and facilitate their acceptance.

High performance low-energy buildings

The era of legislation and creditable methods towards producing sustainable buildings is upon us. Yet, a major barrier to achieving environmental responsive design is in the lack of available information at the programming or pre-design phases of a project. The review and evaluation of climate as well as energy-efficient strategies could be difficult to consider at these preliminary stages. Until recently, introducing energy simulation tools at the design stage has been difficult and perhaps next to impossible at a pre-design or programming stage. However, analysis of this sort is essential to ‘green building rating’ or performance assessment schemes such as LEED (Leadership in Energy and Environmental Design) and BREEAM (Building Research Establishment Environment Assessment Method). This paper discusses the implementation of a particular tool, ENERGY-10, where ‘basecase’ building defaults are compared to a low-energy case which has applied multiple energy-efficient strategies automatically. An annual hour-by-hour simulation provides a daylighting calculation with a subsequent thermal evaluation. Calculation results provide energy consumption, peak load equipment sizing, a RANK feature of the energy-efficient strategies, reporting of CO2, SO2 and NOx reduction, optimum glazing type as well as excellent graphic output. Consideration is given as to the approach of how such information can be introduced into the building project brief enforcing a low-energy
performance target.

Environmental design : incorporating a rating tool into the design of commercial buildings

Environmental performance assessment or green building rating tools for commercial buildings are one of the more recent responses to encourage green solutions for commercial buildings. This paper discusses the initial stages of a research project that looks at the impact of a rating tool, such as Green Star, on design. There are numerous ways in which an architect can design commercial buildings, but environmental design solutions have consistently failed to become accepted practice. Therefore, how will this tool be incorporated into the building design process? Developed to assist the designer can the inclusion of a rating tool such as Green Star provide an effective framework to encourage the inclusion of environmental design strategies in commercial buildings? A field study, recording the design process of a commercial building, anticipates that a whole building assessment approach towards design, as proposed through the Green Star Rating Tool, will provide an effective framework to set and monitor design targets in order to optimise the environmental design goals in commercial buildings.

The business case for incorporating sustainability in office buildings : the adaptive reuse of existing buildings

The effect of climate change and global warming has received increased attention in society with constant reminders about the importance of energy efficiency and sustainability in buildings. Whilst the focus is often placed on smaller items such as plastic bags, air conditioners and motor vehicles, the emphasis has recently shifted to structures in the built environment. Office buildings have been identified as contributing significantly to global warming during their building lifecycle with a substantial contribution to CO2 omissions. In response, building designs and construction techniques have evolved over time to improve energy efficiency and reduce CO2 omissions. Whilst property valuers, managers and analysts must remain up-to-date regarding changes, relatively little research has been conducted about whether and how increased sustainability, such as signified in a Green Star rating affects a property’s highest and best value and long-term lifecycle. This study investigates the degree to which sustainability is understood in the property marketplace, especially in relation to property values with the emphasis placed on a cost- benefit analysis from both an owner’s and tenant’s perspective. Whilst it may be argued that incorporating sustainability into a new office building is cost prohibitive on a financial cost-benefit analysis, often various minor steps can be taken to upgrade the sustainability of an existing building. This project examines recent trends in capital expenditure to increase the sustainability of offices and where Green Star ratings have been applied to establish whether any corresponding increase in value is evident. In order to develop a researchframework, a thorough literature review will be conducted of recent Australian and overseas studies. This will enable links between sustainability and office buildings to be highlighted, and vitally how they affect a property’s value in both the short and long-term.

Investor perception of the business case for sustainable office buildings : evidence from New Zealand

Over recent years the global market for sustainable commercial property has been growing in importance, with rapid growth occurring overseas that has led to substantial changes in the property markets. The New Zealand property industry has been recently introduced to the concept of sustainability, and although still at an early stage is already noticing the accelerating uptake of sustainability in the industry. Although certain measures have been taken by the New Zealand Green Building Council and government mandates, there remains still a common assumption that there is considerable hesitation and skeptism in the market from both an investor’s and a building owner’s perspective.

The research presented in this paper reports on the results of an investigation into the market perception toward sustainable buildings from the investment community in New Zealand. Property developers and investors from New Zealand were surveyed about their perception of sustainable buildings in New Zealand and their actions with regards to their own commercial portfolios, as well as the impact sustainability is having upon investment decisions. This paper presents the results of research conducted into the relationship between the elements of sustainability and the market value of an office building. The paper provides an insight into the rapidly evolving area of sustainability and office buildings, with the emphasis placed on the valuation process that seeks to assess a hypothetical purchaser’s perspective of this relationship.

Residential housing and the green agenda

Australia’s residential development industry is at least superficially embracing environmental and sustainability issues in urban design. Rapidly emerging use of recycled water, lower impact outfalls, the use of roof water and water sensitive design for both housing and landscapes are all trends of interest to the property profession. There is particular interest in the cost of meeting end-user, local Government, State Government and development industry expectations for a green agenda for the residential sector.

Green roof retrofit potential in the central business district

Purpose – The purpose of this paper is to illustrate the potential for green roof retrofit to commercial buildings in a city centre to property managers and other property professionals.

Design/methodology/approach – This paper addresses the research question: what is the potential of existing buildings in the CBD to accommodate a retrofitted green roof? Furthermore, it questions how many buildings are suitable for green roofs? The researchers compile a unique building database incorporating information about 536 commercial buidings and evaluate the potential suitability of each building to undergo a green roof retrofit. Assisted by other commercially available databases and software, the researchers are able to assess each roof based on criteria derived from an extensive literature review.

Findings – A relatively small proportion of roofs are found to be suitable, partly a result of local climate conditions and rainfall patterns, and the physical property stock. On a purely physical assessment, only a very small proportion of CBD stock is found to be suited. These buildings are most likely to be in low secondary locations, ungraded or B grade buildings, privately owned, concrete framed and not overshadowed by adjoining properties.

Practical implications – Property managers and other property professionals can now determine the potential of their portfolio stock for green roof retrofit based on the review of building attributes required for success adaptation in this paper. It possible that greater potential for green roof retrofit exists in the suburbs or regional towns where lower rise buildings may reduce the amount of overshadowing found in city centres. Follow-up research could focus on a comparison of regional and suburban developments.

Originality/value – This is the first study of its kind and has assessed such a large number of buildings for their suitability for green roof retrofit; the findings provide a reliable guide for policymakers regarding the potential number of city centre buildings which would be possible to retrofit. Such findings should influence policymaking and incentives to target effective sustainability policies with regards to existing buildings.

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.