Energy use and thermal comfort in a rammed earth office building

A two-storey rammed earth building was built on the Thurgoona Campus of Charles Sturt University in Albury-Wodonga, Australia, in 1999. The building is novel both in the use of materials and equipment for heating and cooling. The climate at Wodonga can be characterised as hot and dry, so the challenge of providing comfortable working conditions with minimal energy consumption is considerable. This paper describes an evaluation of the building in terms of measured thermal comfort and energy use. Measurements, confirmed by a staff questionnaire, found the building was too hot in summer and too cold in winter. Comparison with another office building in the same location found that the rammed earth building used more energy for heating. The thermal performance of three offices in the rammed earth building was investigated further using simulation to predict office temperatures. Comparisons were made with measurements made over typical weeks in summer and winter. The validated model has been used to investigate key building parameters and strategies to improve the thermal comfort and reduce energy consumption in the building. Simulations showed that improvements could be made by design and control strategy changes.

Office building characteristics and the links with carbon emissions

Purpose – The purpose of this paper is to present research which analysed energy consumption in the Melbourne central business district (CBD) office stock and examined all buildings to identify CO2 emissions in 2005. The rationale was that, by profiling a large group of buildings, it would be possible to identify characteristics of the stock. For example, do older buildings typically emit more CO2 per square metre than newer buildings?
Design/methodology/approach – This research conducted a detailed analysis of all Melbourne CBD office stock to identify which patterns and trends emerged regarding building characteristics and carbon emissions. The study examined variables such as building size, number of employees, occupancy levels, physical characteristics and building age.
Findings – By examining all office stock and aggregating data, the results confirm that it is possible to identify general physical building characteristics and carbon emissions. This research confirmed that clear relationships existed within the Melbourne CBD office stock in terms of building size, age and the density of occupation in relation to CO2 emissions.
Originality/value – Practitioners can apply this knowledge to the professional advice they give to clients to assist in achieving increased energy efficiency in the office stock, for example in refurbishment being conscious that smaller buildings will be generally less energy-efficient than larger ones.

Delivering sustainability in office building refurbishment

The effect of climate change and global warming continues to receive attention with many governments and organisations acknowledging the long-term problems associated with the trend, although offering limited realistic solutions. Office buildings have been identified as a contributor to global warming during the construction phase, however during the building lifecycle there is a greater contribution to CO2 omissions. Whilst various building designs and construction techniques have evolved to improve energy efficiency, the focus has largely been placed on new buildings where it is easier to incorporate change and innovative approaches. However, the proportion of new buildings constructed each year is relatively small in comparison to existing building stock, which requires regular capital expenditure to maintain and attract new tenants within a competitive marketplace. Overall the degree to which capital expenditure for an existing building actually includes energy efficiency is difficult to measure, although appears to lag substantially behind sustainable building techniques for a new building.

This study investigates the degree to which energy efficiency is incorporated into office building refurbishment and capital expenditure, with the emphasis placed on a cost-benefit analysis from both the owner’s and tenant’s perspective. Whilst it may be argued that a newly constructed energy efficient office building may be cost prohibitive, various steps may be taken to upgrade the energy efficiency of an existing building. This project identifies differences between varying levels of capital expenditure to ensure an existing building is more energy efficient, with the emphasis placed on (a) the cost of implementation and (b) the potential for tenants to acknowledge the increased energy efficiency via higher rents. In order to develop a research framework, a thorough literature review was conducted of three disciplines being construction technology, building refurbishment and property management.

Energy and thermal comfort in a rammed earth office building

An analysis was made of the Charles Sturt University Academic Office building at Thurgoona from a thermal comfort and energy viewpoint. It was found that the offices did not meet low energy criteria and some were uncomfortable for 30% to 85% of occupied hours.

Sustainability and within use office building adaptations : a comparison of Dutch and Australian practices

Local Authorities worldwide are encouraging adaptation as a means of reducing building related urban energy consumption and greenhouse gas emissions. The City of Melbourne is promoting the retrofit of 1,200 CBD properties before 2020 with sustainability measures as part of their policy to become a carbon neutral city. Australian cities date from 1837 to the present day whereas some European cities have been inhabited for over two millennia. The concepts of adaptation and evolution of buildings and suburbs is well developed in Europe, though the scale of some of the post war developments has created different forms of building perhaps less adaptable or suited to change. The need to adapt buildings and to reduce environmental footprints becomes more pressing over time as global concentrations of carbon dioxide increase. Is it possible for Europeans to learn from Australian practices and vice averse? Through examination of office building adaptation in Melbourne and Amsterdam, it is possible to learn where similarities and differences exist and where new practices can be shared.

This paper addressed the questions; What are the key attributes influencing adaptations in Melbourne and Amsterdam office buildings, and what are the similarities and differences? Using the Melbourne CBD and Amsterdam as a case study, the research analysed 7393 commercial building adaptations in Melbourne and 98 office buildings in Amsterdam where adaptations were completed. The outcomes of this research show where similarities and differences exist and are relevant to all urban areas where adaptation of existing office buildings can mitigate the impacts of climate change and enhance the city for another generation of citizens and users.

Performance study of a daylight guiding system in an office building

This research developed a comprehensive evaluation of a daylight-guiding system in an Australian office building. On-site measurements, simulation and correlation studies have been carried out to identify the daylight contribution from the reflective louvre system. Results show that the system can provide up to 70% additional illuminance for the workplace.

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.

Energy analysis of the construction of office buildings /by Graham J. Treloar

Buildings have a significant impact on the environment due to the energy required for the manufacture of construction materials. The method of assessing the energy embodied in a product is known as energy analysis. Detailed office building embodied energy case studies are very rare. However, there is evidence to suggest that the energy requirements for the construction phase of commercial buildings, including the energy embodied in materials, is a significant component of the life cycle energy requirements. This thesis sets out to examine the current state of energy analysis, determine the national average energy intensities < i.e. embodied energy rates < for building materials and assess the significance of using national average energy intensities for the energy analysis of a case study office building. Likely ranges of variation in the building material embodied energy rates from the national averages are estimated and the resulting distribution for total embodied energy in the case study building simulated. Strategies for improving the energy analysis methods and data are suggested. Detailed energy analysis is shown to be a useful indicative method of quantifying the energy required for the construction of buildings.

Evaluating the whole-life cost implication of revocability and disruption in office retrofit building projects

Retrofit buildings are becoming popular in the United Kingdom as well as many parts of the advanced economies. Existing whole-life costing models have however, not proven to be robust enough to deal with building retrofit scenarios. Recent research has made a case for the existence of revocability and disruption in building retrofit investments. This paper evaluates the whole-life cost implication of revocability and disruption in office retrofit building projects. The potential implication of revocability and disruption are evaluated based on probability and fuzzy logic principles respectively. Two case study projects are selected to appraise the economic potentials of revocability and disruption. It was found that the average cost of revocability relative to the initial capital cost can be up to 119% over a 60-year life. It was also found that the average cost of disruption relative to the initial capital cost can be up to 12%. Future studies will utilise sensitivity analysis in assessing the relative preference of building retrofit configurations in office building projects. The external validity of this work is moderate, as the intention is to establish analytical generalisation rather than statistical generalisation for office retrofit building projects.

An assessment of the energy and water embodied in commercial building construction

Growing global concern regarding the rapid rate at which humans are consuming the earth’s precious natural resources is leading to greater emphasis on more effective means of providing for our current and future needs. Energy and fresh water are the most crucial of these basic human needs. The energy and water required in the operation of buildings is fairly well known. Much less is known about the energy and water embodied in construction materials and products. It has been suggested that embodied energy typically represents 20 times the annual operational energy of current Australian buildings. Studies have suggested that the water embodied in buildings may be just as significant as that of energy. As for embodied energy, these studies have been based on traditional analysis methods, such as process and input-output analysis. These methods have been shown to suffer from errors relating to the availability of data and its reliability. Hybrid methods have been developed in an attempt to provide a more reliable assessment of the embodied energy and water associated with the construction of buildings. This paper evaluates the energy and water resources embodied in a commercial office building using a hybrid analysis method based on input-output data. It was found that the use of this hybrid analysis method increases the reliability and completeness of an embodied energy and water analysis of a typical commercial building by 45% and 64% respectively, over traditional analysis methods. The embodied energy and water associated with building construction is significant and thus represents an area where considerable energy and water savings are possible over the building life-cycle. These findings suggest that current best-practice methods of embodied energy and water analysis are sufficiently accurate for most typical applications, but this is heavily dependent upon data quality and availability.

Indoor environment quality and occupant productivity in the CH2 building

This paper presents a summary of the results from a post-occupancy evaluation study on indoor environment quality (lEO) and occupant health, wellbeing and productivity in the Council House 2 (CH2) building, which is owned and occupied by the City of Melbourne. This case study has highlighted that the productivity of office building occupants can potentially be enhanced through good building design, and provision of a high quality, healthy, comfortable and functional interior environment, that takes account of basic occupant needs.

A method for evaluating workplace utility

Acquiring office buildings that provide the required level of utility, and maintaining the buildings in that state, should be a priority for any organisation. Failure to do so may give rise to increased churn, reduced productivity, higher employee turnover, increased staff absenteeism and rising health care costs related to heightened stress. There is, however, no single measure of office building utility. Discusses the development of a valid and reliable scale for measuring the utility of public sector office buildings. Data collection involved the use of focus groups and an online survey of 1,800 building occupants. The findings suggest that the utility of public sector office buildings can be measured using a 22-item scale comprising four dimensions. The potential applications of the scale and its use in current research are examined.

The increasing importance of sustainability for building ownership

Purpose — This study seeks to investigate the degree to which energy efficiency is incorporated into office building refurbishment and capital expenditure with the emphasis placed on a cost-benefit analysis from the owner’s perspective.
Design/methodology/approach – In order to develop a research framework, a thorough literature review was conducted of three disciplines being construction technology, building refurbishment and property management. The study identifies differences between varying levels of capital expenditure to ensure an existing building is more energy efficient, with the emphasis placed on the cost of implementation and the potential for tenants to acknowledge the increased energy efficiency via higher rents.
Findings – Office buildings have been identified as a contributor to global warming during the construction phase, however during the building lifecycle there is a greater contribution to CO2 omissions. Whilst various building designs and construction techniques have evolved to improve energy efficiency, the focus has largely been placed on new buildings where it is easier to incorporate change and innovative approaches. However, the proportion of new buildings constructed each year is relatively small in comparison to existing building stock, which requires regular capital expenditure to maintain and attract new tenants within a competitive marketplace.
Practical implications – The increasing importance of energy efficiency affects the office market in a variety of different ways.
Originality/value – This paper identifies important links between the environment and the built environment, and the implications for office building owners.