Regulations and robust low-carbon buildings

Building regulations and associated calculation methods have been rapidly evolving, driven in Europe by the European Union Energy Performance of Buildings Directive. As an example, the current UK regulations are explored in relation to buildings that are naturally ventilated, mechanically ventilated, or mechanically ventilated and cooled. The UK regulatory energy and carbon calculation methods are investigated using a standard office design with typical, best practice, and advanced building fabric and systems applied. The criteria and calculations for demonstrating avoidance of excessive temperatures in buildings that have no mechanical cooling are also explored. Observations are made on how the regulations may influence future adoption of mechanical cooling. Current regulatory methods can be subjective and limited in scope. For example, they do not include adaptive comfort criteria or uncertainties in parameters such as occupant behaviour, climate, internal gains from equipment, etc. A design methodology is proposed that addresses these issues and provides a capability parameter to quantify robustness. This capability parameter allows comparison of design options and provides an indication to building users of the limitations to a building's use beyond which mitigating action would have to be taken for performance to be maintained

Simulation and BIM in building design, commissioning and operation: a comparison with the microelectronics industry

Analogy between the Microelectronics and Building industries is explored with the focus on design, commissioning and operation processes. Some issues found in the realisation of low energy buildings are highlighted and techniques gleaned from microelectronics proposed as possible solutions. Opportunities identified include: adoption of a more integrated process, use of standard cells, inclusion of controls and operational code in the design, generation of building commissioning tests from simulation, generation of building operational control code (including self-test) from simulation, inclusion of variation and uncertainties in the design process, use of quality processes such as indices to represent design robustness and formal continuous improvement methods. The possible integration of these techniques within a building information model (BIM) flow is discussed and some examples of enabling technologies given

Thermal mass, insulation and ventilation in sustainable housing - An investigation across climate and occupancy

Sustainable housing standards are reviewed including the UK 2005 building regulations, the UK Advanced Standard and EU Passive-house Standard. Conflicts between the standards are highlighted. The significance of insulation, orientation, ventilation, thermal mass, occupancy, gains, shading and climate on predicted energy performance is illustrated. An ESP-r model is then used to investigate these factors across a range of climates and occupancy / gains scenarios. The investigation covers both heating and cooling energy requirements. The relative importance of key factors is quantified and a matrix of results presented with conclusions. The role of simulation in informing design decisions is demonstrated as well as the importance of considering climate and occupancy/ gains patterns

Embracing variations in patterns of use, pre and post design phase, to improve tenant energy performance

This paper elaborates a new energy performance benchmarking method to support green tenancy agreements and other energy performance contracts. The existing national energy reporting method does not categorise systemic variations in patterns of use. Results of a case study monitoring operational data of a multi-tenanted office building are presented. The data reveals the actual designed spectrum of occupant density accounts for a 44% increase in tenant energy demand per square meter and a 112% increase in tenant energy demand per full time employees [FTE], dramatically affecting the buildings internal gains, heating and cooling requirements. The study highlights how low levels of occupancy and extended operational hours can give a false representation of energy efficiency

IEQ Performance gaps : Failure modes, litigation risks, and the need for quality

There is much evidence that current building industry process does not deliver the intended outcomes1. Performance gaps exist including IEQ failures which have resulted in litigation. These performance gaps and litigation are likely to increase due to the move towards more advanced buildings and systems, changes in local weather, and the increasing availability and use of post occupancy performance monitoring. While there are many initiatives aimed at improving industry process, none of these directly address the quality issues2. It is proposed that a quality systems approach similar to that of other more performance sensitive industries could provide a solution

Air-conditioning : the impact of UK regulations, the risks of unnecessary air-conditioning and a capability index for non-air-conditioned naturally ventilated buildings

The UK building regulations have been rapidly evolving. New methodologies have been developed in part driven by the EU EPBD. In this paper the UK building regulations and energy performance calculations as they relate to naturally ventilated (NV), mechanically ventilated (MV) and air conditioned (AC) buildings are reviewed. Calculations are carried out for typical, best practice and advanced fabric and systems and observations made on how the results may influence future adoption of air conditioning. Calculations of overheating potential and risks of unnecessary air-conditioning are discussed. A design methodology is proposed that could help to address some of the risks and provide a capability parameter to quantify design quality and allow design comparison

Why advanced buildings don't work?

The intent of policy is to achieve robust comfortable low energy buildings. However there are obvious policy disconnects and, where there is evidence, it appears that in general advanced buildings do not achieve their intended performance. There are many industry and policy initiatives aimed at improving industry processes such as: Soft Landings, BREEAM, LEED, Green Star, AGBR and BIM. In this paper the performance of buildings likely to be promoted by current policy is investigated and a number of significant and recurring problems identified. The possibility that these problems will be resolved by current initiatives is discussed and it is concluded that important gaps remain to be addressed

Facing the growing problem of the electric power consumption in Egyptian residential building using building performance simulation program

Egypt has been experiencing recurrent power cuts especially at the summer, with the problem being made worse by the extra demands placed on the electrical grid by the advent of the holy month of Ramadan. Electricity shortages are now a problem in Cairo, Alexandria, Sohag, Qena, Luxor, Aswan, and Nubia, as well as in the Nile Delta governorates of Beheira and Qalioubiya. The aim of this study is to develop a model for the Egyptian residential building using Building Performance Simulation Program and make sensitivity analysis on some variables effecting the electric power consumption in order to help faceting the growing problem in Egypt. The model was created using the IES-VE 2012 (Integrated Environmental Solution ). The simulation model was verified against the survey data for the Egyptian apartment and same model simulated using energy Plus simulation tool. The results of the program describing different situations for energy using profile for the air conditions, lighting and equipments in respect to building layout and construction climate and pattern of use. This model can be used in the future to help in reducing the electric power consumption in the residential building

Local Energy Perspectives on Scotland and Brazil

Policy support for climate change and sustainable energy deployment in the EU and Scotland has enabled Communities to implement and benefit from local energy schemes, there would appear to be potential for similar schemes in Brazil. There have however been miss-steps due to narrow criteria being applied in assessment of carbon emissions and sustainability, there is a need for more detailed environmental assessment. The ability of a Community to adopt a local energy scheme depends on its Governance, financial and technical capacity. A new multi-disciplinary assessment process is being developed and piloted in Scotland and Brazil which includes technical, environmental and socio-economic factors. The output will be an identification of appropriate energy systems and technical and socio-economic gaps to be addressed. The focus here is on local energy due to global funding availability however the Community capabilities developed for energy schemes can be applied to other projects and have wide benefits

Development and validation of detailed building, plant and controller modelling to demonstrate interactive behaviour of system components

As plant modelling becomes capable of more complexity and detailed resolution, new opportunities arise for the virtual evaluation of discrete plant components such as flow control and energy conversion devices, and controllers. Such objects are conventionally developed and tested at the prototype stage in a laboratory environment. Designers now seek to use modelling technology to extend their understanding from limited laboratory test results to full building and plant system analysis. This paper describes the development of a modelling system, using ESP-r, for typical United Kingdom domestic house types with hydronic gas or oil fired central heating including radiator and underfloor heating systems, and with a variety of conventional or advanced control types. It demonstrates the ability of detailed building and plant modelling to reveal unexpected insights into how real control systems perform in combination with other plant items and in different building types, including estimation of their influence on annual energy consumption. Comparisons with measurements taken in test rooms confirm that the observed behaviour of controls is realised in practice. The authors conclude that the complex dynamic interactions that take place between the various elements that make up a real building energy system have an important influence on its overall energy performance, revealing causes of variance that cannot be identified by laboratory testing alone, or by simplistic energy assessment tools