Model-based life cycle cost and assessment tool for sustainable building design decision

There is a growing concern in reducing greenhouse gas emissions all over the world. The U.K. has set 34% target reduction of emission before 2020 and 80% before 2050 compared to 1990 recently in Post Copenhagen Report on Climate Change. In practise, Life Cycle Cost (LCC) and Life Cycle Assessment (LCA) tools have been introduced to construction industry in order to achieve this such as. However, there is clear a disconnection between costs and environmental impacts over the life cycle of a built asset when using these two tools. Besides, the changes in Information and Communication Technologies (ICTs) lead to a change in the way information is represented, in particular, information is being fed more easily and distributed more quickly to different stakeholders by the use of tool such as the Building Information Modelling (BIM), with little consideration on incorporating LCC and LCA and their maximised usage within the BIM environment. The aim of this paper is to propose the development of a model-based LCC and LCA tool in order to provide sustainable building design decisions for clients, architects and quantity surveyors, by then an optimal investment decision can be made by studying the trade-off between costs and environmental impacts. An application framework is also proposed finally as the future work that shows how the proposed model can be incorporated into the BIM environment in practise.

From CAD to virtual reality: modelling approaches, data exchange and interactive 3D building design tools

Virtual reality has the potential to improve visualisation of building design and construction, but its implementation in the industry has yet to reach maturity. Present day translation of building data to virtual reality is often unidirectional and unsatisfactory. Three different approaches to the creation of models are identified and described in this paper. Consideration is given to the potential of both advances in computer-aided design and the emerging standards for data exchange to facilitate an integrated use of virtual reality. Commonalities and differences between computer-aided design and virtual reality packages are reviewed, and trials of current system, are described. The trials have been conducted to explore the technical issues related to the integrated use of CAD and virtual environments within the house building sector of the construction industry and to investigate the practical use of the new technology.

Energy efficient building design

This chapter covers the basic concepts of passive building design and its relevant strategies, including passive solar heating, shading, natural ventilation, daylighting and thermal mass. In environments with high seasonal peak temperatures and/or humidity (e.g. cities in temperate regions experiencing the Urban Heat Island effect), wholly passive measures may need to be supplemented with low and zero carbon technologies (LZCs). The chapter also includes three case studies: one residential, one demonstrational and one academic facility (that includes an innovative passive downdraught cooling (PDC) strategy) to illustrate a selection of passive measures.

Post-occupancy evaluation studies in recently refurbished office building: energy performance and employees' satisfaction

Existing buildings contribute greatly to global energy use and greenhouse gas emissions. In the UK, about 18% of carbon emissions are generated by non-domestic buildings; sustainable building refurbishment can play an important role in reducing carbon emissions. This paper looks at the performance of a recently refurbished 5-storey office building in London, in terms of energy consumption as well as occupants’ satisfaction. Pre- and post-occupancy evaluation studies were conducted using online questionnaire surveys and energy consumption evaluation. Results from pre-occupancy and post-occupancy evaluation studies showed that employees, in general, were more satisfied with their work environment at the refurbished building than with that of their previous office. Employees’ self-reported productivity improved after the move to Elms House. These surveys showed a positive relationship between employees’ satisfaction with their work environment and their self-reported productivity, well-being and enjoyment at work. The factor that contributed to increasing employee satisfaction the most was: better use of interior space. Although the refurbishment was a success in terms of reducing energy consumption per m2, the performance gap was almost 3 times greater than that estimated. Unregulated loads, problems with building control, ineffective use of space and occupants’ behaviour are argued to be reasons for this gap.

Auditing construction costs during building design : a case study of cost planning in action

Building cost planning was originally developed in the framework of traditional procurement methods with conventional documentation, tendering and administration processes. With the advent of alternative forms of procurement with more fluid approaches to design stages and documentation, the need for sound cost planning does not appear to diminish. As a process established on solid theoretical foundations, cost planning should be robust enough to adapt and flourish in a variety of procurement environments. However, little documentation and analysis of transformed and adapted forms of cost planning appear to have been made. This case study of a design-construct company in Melbourne, Australia, presents and explores a contemporary form of building cost planning integrated into a design cost management approach adopted by a construction company experienced in alternative forms of procurement. The article traces this process on a design-construct project from inception to the end of the design development stage and tender. Whilst the fundamental framework of cost planning remains intact, the focus and detail in each of the stages are guided by the company's priority for greater financial control over the cost and value implications of design and other decisions. This recently established working model of design cost management in this company has been designed to deliver added value to the client through a better balance of time, cost and quality in each project.

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.

Evaluation of an environmental rating tool for commercial building design

This research examined the inclusion of environmental rating tools in the design of commercial buildings. Environmental issues are becoming increasingly important for designers and the results of the study suggest that rating tools can be an asset to design teams, provided they are integrated and reinforced throughout the design process.

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.