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According to current climate change predictions for the UK, summers are expected to become dryer and hotter in the future. This has potentially serious implications for overheating of naturally ventilated office buildings, many of which already fail to perform under current heatwave conditions. This thesis addresses the summer performance of such buildings under current and future climates by means of building performance simulation. Current industry standard weather datasets for building performance simulation are not however, suited to the assessment of the potential impacts of a changing climate. This work describes the integration of future climate scenarios into widely used weather file formats and critically assesses the resulting weather datasets. Simulations of a case study building at the University of Southampton highlight the potential impact of climate change on future summer overheating inside naturally ventilated buildings. The results of these simulations are compared to monitored data from the case study building during an extended heatwave period in the summer of 2006. It is shown that the present day performance of a naturally ventilated building under an extended heatwave period can give an indication of its likely performance during a projected typical hot summer in the 2050’s under a medium-high emissions scenario. A second case study building serves to highlight that building designs and building services solutions which are suitable for retaining acceptable indoor comfort levels during current heatwave periods, are likely to be suitable to alleviate summer overheating under the predicted warmer future climates. Further simulations, encompassing various locations throughout the UK emphasize the need for timely refurbishment of naturally ventilated office buildings within the next few decades to avoid increasing numbers of existing buildings failing to perform under the predicted future summer conditions.

This thesis delivers a significant contribution to knowledge through the construction of a validated framework, that supports value creation for the QS organisation, when adopting and implementing BIM. It also reports on the current misconceptions in terms of the threat posed by Building Information Modelling (BIM) to the QS profession. This research has found that the QS role will evolve and transform with the opportunities that BIM presents, and will survive as consequence of value creation. The thesis identified 9 critical success factors, 5 success factors specific to BIM and 4 success factors specific to the organisation, all of which contributed towards the development of the framework. The study was conducted by adopting a mixed methods design by extracting knowledge from the literature review to inform the semi structured interviews, the results of which informed the design of the questionnaires and finally all results informed the development of the framework which was finally validated via a focus group. The major findings of this research were threefold. Firstly, from a theoretical perspective it was found that a unified understanding of BIM definition aligning the perceptions of the individual QS with those of the organisation, was the foundation from which to develop the framework. It was found to be of far more significance than most theorist purport, as the adoption process requires systemic transformation at all levels within the organisation, based on a unified vison. This stems from individual and organisational perceptions of BIM, which in turn go back to definition. Secondly, the research identified that the BIM barriers reported by the theorists are not the dominant barrier to implementation, but it is more specifically the lack of understanding of the benefits of BIM to the individual, that restrict adoption. Finally, the research has provided the QS organisation with a holistic overview of the key critical success factors necessary to support BIM level maturity and ultimately value creation.

Fast urban growth and topographical factors across Europe have contributed to an increase in the total number of hillside residential buildings. In the case of Portugal, a clear need for hillside building design which can fully benefit from the thermal advantage of slope terrains has been identified. Although the energy efficiency of ground-integrated architecture has been the subject of numerous research works, only a small number of those research projects have focused on the thermal potential of ground-integrated buildings constructed on sloped terrains. The research presented in this thesis sheds light on the energy saving potential of ground-integrated buildings on slope terrains and provides design guidelines based on the research findings. Firstly, through mathematical calculations, this research demonstrates that ground thermal patterns under slope terrains are different from those below flat areas. In Lisbon, terrain inclinations have higher annual ground thermal potential than flat terrains. It is furthermore noted that a transitional zone is formed immediately before and after a slope. As a result of these investigations it is concluded that slopes of 30° to 40° provide the best annual ground thermal potential. Secondly, through a parametric study using EnergyPlus to simulate ground heat transfer, it is show that ground integration affects buildings thermal performance. It is found that the greater the ground integration the lower the energy demand, but also that total ground integration fails to provide the best solution. Concerning the levels of slope integration, the steeper the slope, the greater the average annual savings. However the thermal advantage difference between steeper slopes such as those of between 30° to 50° is small. Regarding the impact of building design on annual saving potential, it is found that building design does affect models’ thermal performance and that its impact is greatest with shallower slopes. It is therefore concluded that in temperate climates, new hillside constructions can take advantage of the energy saving potential of ground integration into slope terrain and of slope building designs.

Research relating to the potential impacts of climate change on UK housing has increased in recent years. The future performance of dwellings that are currently considered sustainable may change under a changing climate. For example, well insulated, air tight homes that are energy efficient and comfortable now may be at risk of overheating in the future. Decision-making for sustainable house designs may become more challenging regarding dwellings that will perform well now and be resilient to climate change risks, such as overheating, in the future. This study evaluates the effect of overheating risk and future climatic uncertainty in designing UK dwellings. The main focus of the research is on the thermal performance of the external building envelope. The foremost aim is to future proof current designs in order to provide the best possible thermal comfort under likely warmer weather conditions produced by climate change. This research examines a number of constructional design options to reduce energy consumption and improve thermal comfort on the basis of climate change predictions up to 2080. The study develops a methodology by means of computer simulations to assess and predict the performance (in terms of total energy input, both heating and cooling, required to maintain thermal comfort) in a range of current, ‘high performance’ construction systems used on simple and typical UK house models in London and Manchester. The findings of this study show that UK sustainable homes, in their present format, are susceptible to a future overheating risk. It is argued that the substantial part of the overheating risk can be alleviated by the integration of modern smart materials and conventional design solutions, such as shading devices and earth-to-air heat exchangers (EAHE). The research also proposes a new method of integrating phase change materials into the building envelope to reduce domestic cooling loads and overheating hours in the coming decades.

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The present research is concerned with investigating the structural effect of using steel fibre-reinforcement on the punching shear behaviour of ground-suspended slabs with internal columns. The main objectives of this research were to develop a constitutive model for steel fibre-reinforcement (SFRC), to study experimentally the punching shear behaviour of SFRC with no longitudinal reinforcement and to develop a finite element model that can accurately predict the behaviour of SFRC slabs subjected to punching shear. In this respect, a literature review of the work undertaken by previous researchers on punching shear behaviour of concrete slabs is presented. After that, a constitutive model for SFRC was developed. This is followed by a preliminary finite element analysis (FEA) and experimental study of SFRC slabs. Finally, a finite element model was developed. The literature review revealed that little work has been carried out to study the effect of fibre-reinforcement on the punching shear capacity of concrete slabs. Furthermore, structures, hence a thorough investigation in this area was mandatory. A constitutive model for SFRC in post-cracking stage was developed. This enables one to estimate the tension stiffening behaviour of SFRC based on a simple beam bending test and a statistical model developed in this research, this constitutive model was used later on in the modelling of the SFRC slabs using FEA. In the preliminary FEA, sufficient information for the size and the design of test specimens that were used in the experimental programme was produced. In the experimental study, eight steel fibre-reinforced concrete slab-column connection specimens were tested. The variables of the test specimens include the concrete compressive strength, fibre dosage and fibre aspect-ration.

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The ambition of the thesis was to consider the performance of urban dwellings, and more specifically to develop a series of benchmarked criteria that holistically define the performance of an urban dwelling throughout its lifecycle, then to create an assessment tool that extends the scope of existing environmental evaluation models. The benchmarks for each of the criteria define the quantitative and qualitative performance values of firstly, a dwelling built to current regulation standards, secondly a European comparison, and thirdly one of the drawn studies undertaken as part of the research methodology; finally the performance of the 'urban house in paradise' is proposed, based upon advances to the above. These benchmarks provide a generic framework that describes the integrated performance of adwelling. The tool advances existing assessment models by responding to their identified shortcomings, which includes taking account of the interrelation between criteria and evolves significance weightings in terms of the relative priority of the criteria to each other. By attempting to resolve the linkages between the criteria, the tool as developed will model how these interrelated benchmarks effect each other within agiven project, so that a holistic set of vaJues, the ideal balance of priorities, can be developed. This will enable a designer to determine the best overall balance of a dwelling's performance, taking account of the identified relative significance of each of the criteria, to bring the sustainability of a project as close as possible to the idealo f the 'urban house in paradise'.S uch a development provides an advance upon existing techniques in defining and assessing the ecological performance of adwelling. The contributions to knowledge made by this thesis are primarily in increasing the depth and scope of assessing the performance, and in particular the environmental performance, of dwellings. The field of criteria in existing environmental assessment methods is extended to include not only a broader, and therefore more holistic range than any other environmental assessment model, but also those relevant to socio-economic areas of sustainability. Prioritisation and interrelation between the individual criteria was developed in the assessment tool's methodology: interrelation is crucial, as sustainability demands a holistic view. Assessment and prioritisation methods are based on the philosophy of Deep Ecology, and not an anthropocentric orientation, therefore potentially creating a radical reappraisal of the criteria considered important in other assessment models. The prioritisation extends between fields, in search of most significant criteria within a holistic view and has identified, within the boundaries of what is technically feasible, the criteria that can contribute most to achieving more ecologically sustainable dwelling in a Deep Ecological sense.

Daylight is an energy efficient solution for illumination and visual comfort in buildings. However, successful daylight design requires effective daylight control technology to eliminate the negative impact such as overheating, unbalanced indoor daylight distribution and glare. With this mind, the current thesis presents a novel multifunctional roof panel which might be applied in atrium and large green house. The working principle of the panel is based on the non-imaging low-concentration solar collector: dielectric Compound Parabolic Concentrator (CPC). Detailed study on the dielectric CPC has found that there would be some light escaping from side wall of CPC when the incident light is beyond CPC acceptance angle, which could actually be used for indoor daylight provision; while the incident light concentrated on the base of CPC could be used for concentrating PV application. Thus a dielectric CPC panel which consists of several trough dielectric CPC rods is designed and manufactured, its function of hybrid PV/Daylight is investigated through PHOTOPIA simulation and outdoor testing, both simulated and measured results showed that under sunny condition, only 10-15% of light could be transmitted through the panel in cooling season, and the rest of the light is used for concentrating PV application; while light transmittance of about 40-60% is achievable in winter period, when daylight is desired. Additionally, constant light transmittance of about 40% is achievable under overcast sky. The above figures could verify the seasonal daylight control ability of the panel. On the other hand, for the designed panel, the rejected heat on PV could still flow into the building. As a result, a PV/Thermal system is designed to remove the rejected heat on PV cell and reutilize it for thermal application such as food drying. The design parameter such as approach velocity, pitch distance, and perforation porosity are numerically investigated by CFD simulation. The prototype of the system is built and measured under solar simulator and real sky. Both simulated and measurement results showed that the heat recovery efficiency could be 40-80% depending on different geometries and approach velocities; and little amount of rejected heat could transfer from the PV cell to the building interior. The hybrid PV/Thermal application seems to be achievable. Lastly, the energy and economic performance for the EW-orientated dielectric CPC panel is investigated using new proposed concept of “inner south projection angle” and its correlation with the CPC optical performance, the building energy simulation software EnergyPlus and its weather data are also employed. An example case on an educational building with a central atrium in Nottingham shows that: compared to the conventional double glazing window, there is 55% increase in useful daylight illuminance (500-2000lux) percentage; 81.5% reduction in window solar heat gain in cooling season and only 10.78% reduction in window solar heat gain in heating season; there is also a power generation of 290.65W/m2 from PV cells; and the estimated payback period is less than 5 years. Therefore, the proposed multifunctional roof panel for PV/Thermal/Daylight application could comprehensively utilise the solar energy and provide comfort thermal and visual indoor environment.