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Several studies have demonstrated the capability of data-driven modelling based on on-site measurements to characterise the thermal performance of building envelopes. Currently, such methods include steady-state and dynamic heating experiments and have mainly been applied to scale models and unoccupied test buildings. Nonetheless, it is proposed to upscale these concepts to characterise the thermal performance of in-use buildings based on on-board monitoring (OBM) devices which gather long-term operational data (e.g., room temperatures, gas and electricity consumption...). It remains, however, to be proven whether in-use data could be a cost-effective, practical and reliable alternative for the dedicated tests whose more intrusive measurements require on-site inspections. Furthermore, it is presently unclear what the optimal experimental design of the OBM would be and which data analysis methods would be adequate. This paper presents a first step in bridging this knowledge gap, by using on-board monitoring data to characterise the overall heat loss coefficient (HLC) [W/K] of an occupied, well-insulated single-family house in the UK. With the aid of a detailed building physical framework and specifically selected data subsets a sensitivity analysis is carried out to analyse the impact of the measurement set-up, the duration of the measurement campaign and the applied data analysis method. Although the exact HLC of the building is unknown and no absolute errors could hence be calculated, this paper provides a new understanding of the decisions that have to be made during the process from design of experiment to data analysis. It is demonstrated that such judgements can lead to differences in the mean HLC estimate of up to 89.5%. [ABSTRACT FROM AUTHOR]

• Overheating regulations and calculation methods in 26 European countries were compared. • Most of the existing calculation methods are outdated and do not fit climate-proof buildings. • France requires a mixed-mode operation of naturally ventilated households. • The UK developed a heatwave-based calculation approach. • Comfort-based, multi-zonal, and time-integrated calculation approaches are needed. With the ongoing significance of overheating calculations in the residential building sector, building codes such as the European Energy Performance of Building Directive (EPBD) are essential for harmonizing the indicators and performance thresholds. This paper investigates Europe's overheating calculation methods, indicators, and thresholds and evaluates their ability to address climate change and heat events. e study aims to identify the suitability of existing overheating calculation methods and propose recommendations for the EPBD. The study results provide a cross-sectional overview of twenty-six European countries. The most influential overheating calculation criteria are listed the best approaches are ranked. The paper provides a thorough comparative assessment and recommendations to align current calculations with climate-sensitive metrics. The results suggest a framework and key performance indicators that are comfort-based, multi-zonal, and time-integrated to calculate overheating and modify the EU's next building energy efficiency regulations. The results can help policymakers and building professionals to develop the next overheating calculation framework and approach for the future development of climate-proof and resilient residential buildings. [ABSTRACT FROM AUTHOR]

Abstract: The climate in cities differs significantly from those found in the surrounding area. These differences results from modifications of the Earth''s surface that alters the disposition of “natural energy balance” at a micro-scale and the concentration of activities that results in anthropogenic emissions that change the composition of the atmosphere. These urban effects have distinctive temporal and spatial properties with different impacts on building energy performance depending on their purpose which are rarely accounted for. This paper examines performance implications of a change-of-use (from office to residential) in the context of the UK government''s proposal to encourage regeneration and to meet housing needs. However, the diurnal occupation and activity patterns of these uses are distinct. For office buildings, with daytime occupation, focus is on the diurnal heating cycle driven by solar energy gains to which internal energy sources must be added. For residential buildings occupation and activity are primarily associated with the diurnal cooling period, and lower levels of activity that results in a primary heating need. This paper highlights the link between the timing of the urban climate effects, the urban setting and energy performance in a typical city street, where buildings are currently designed for commercial use. It employs London''s current and projected climate to simulate heating and cooling demands. By studying the role of urban form and its implications on the suitability of a buildings function we find that a ‘form first’ approach should be considered in the early design stages over the standard ‘fabric first’ approach. [Copyright &y& Elsevier]

Affecting millions of Europeans, energy poverty is increasingly high on the political agenda. This paper compares space and water heating demand at household level in Germany and in the United Kingdom (UK) between 1991 and 2015. The elasticities of consumption of space and water heating with respect to price, income and heating degree days (HDD) are examined using non-parametric models. Domestic heating consumption is highly elastic with HDD in both countries and HDD elasticities are found to be higher in the UK. From a certain income threshold, heating demand decreases as income increases in German households whereas demand rises with higher incomes in the UK. High price elasticities indicate that UK households are very responsive to energy conservation measures, therefore implying that a pricing policy will effectively reduce heating consumption. However, in Germany, the impact of pricing policies is unclear. Thus, the most effective policy measure to decrease domestic heating consumption in Germany in the long-run should be one which targets improvements of building envelope performance levels. [ABSTRACT FROM AUTHOR]

Wind-driven rain (WDR) is rain given a horizontal velocity component by wind and falling obliquely. It is a prominent environmental risk to built heritage, as it contributes to the damage of porous building materials and building element failure. While predicted climate trends are well-established, how they will specifically manifest in future WDR is uncertain. This paper combines UKCP09 Weather Generator predictions with a probabilistic process to create hourly time series of climate parameters under a high-emissions scenario for 2070–2099 at eight UK sites. Exposure to WDR at these sites for baseline and future periods is calculated from semi-empirical models based on long-term hourly meteorological data using ISO 15927-3:2009. Towards the end of the twenty-first century, it is predicted that rain spells will have higher volumes, i.e. a higher quantity of water will impact façades, across all 8 sites. Although the average number of spells is predicted to remain constant, they will be shorter with longer of periods of time between them and more intense with wind-driven rain occurring for a greater proportion of hours within them. It is likely that in this scenario building element failure – such as moisture ingress through cracks and gutter over-spill – will occur more frequently. There will be higher rates of moisture cycling and enhanced deep-seated wetting. These predicted changes require new metrics for wind-driven rain to be developed, so that future impacts can be managed effectively and efficiently. [ABSTRACT FROM AUTHOR]

Given the complexity and interconnection of different aspects involved in building evaluation, one of the most relevant, and challenging, research topics is the integration of different domain models (such as thermal comfort, indoor environmental quality and occupant comfort) to effectively describe and inform improvement strategies for the behaviour and performance of a building and building stock. Currently, this problem is unsolved with only one study attempting to integrate building energy simulation and life cycle assessments (separately, both practices are utilised to facilitate the design and management of buildings, traditionally consultancies offer building energy simulation services – most commonly for regulatory purposes – and more recently life cycle impact assessments), whilst no work has attempted this integration in a dynamic manner. This study addresses this gap by developing a dynamic, open building information modelling based co-simulation architecture. This architecture is the first to tightly couple and integrate EnergyPlus and Brightway2, in a way that does not rely upon heuristics or simplified tools. Furthermore, it is the first building energy simulation and life cycle assessment co-simulation to enable time-differentiated (dynamic) results and the first to be enabled only by open technologies. The architecture has been validated against two case-study non-domestic buildings located in the United Kingdom and Luxembourg, demonstrating its applicability to the construction and operational life cycle phases of buildings. The work presented in this paper has shown how a time-differentiated co-simulation approach across energy and lifecycle domains enables a more holistic analysis of whole buildings with greater accuracy and granularity. • There is a lack of studies co-simulating building energy simulation and life cycle assessment. • This study develops an open, building information modelling based co-simulation architecture. • The developed co-simulation architecture tightly couples whole building energy simulation and life cycle assessment models. • Co-simulation architecture has been validated against two non-domestic buildings, in the United Kingdom and Luxembourg. • The developed architecture enables time-differentiated (dynamic) life cycle assessment results. • Time-differentiated life cycle assessment results provide results at a finer level of granularity and accuracy. [ABSTRACT FROM AUTHOR]

This paper empirically investigates the influence of building fabric, services and occupant related factors on actual energy use of six case study dwellings, located in three new low energy social housing developments in UK, covering a variety of built forms and construction systems (timber frame, hempcrete, steel-frame). Physical monitoring of indoor environment and window-opening is cross-related with building fabric and systems’ performance, and qualitative data gathered through occupant surveys, review of control interfaces and handover guidance, to understand the causes of the gap between modelled and measured energy use. Actual energy use is found to exceed design expectations by a factor of three, questioning the need for whole-house mechanical ventilation heat recovery (MVHR) systems at measured air permeability rates of 6 m³/(h.m²) against the design target of 3 m³/(h.m²). Lack of proper commissioning of MVHR and heating systems, combined with inadequate user comprehension about their operation and control leads to occupant ‘misuse’ wherein systems are de-activated, thereby negatively affecting indoor air quality. This is confounded by occupant factors related to higher demand temperatures, unexpected opening of windows during winters due to under-performance of MVHR combined with habitual behaviours, and over-use of heating systems to compensate for higher than expected air permeability. [ABSTRACT FROM AUTHOR]

This paper presents new evidence from a nationwide cross-project meta-study investigating the magnitude and extent of the difference between designed and measured thermal performance of the building fabric of 188 low energy dwellings in the UK. The dataset was drawn from the UK Government’s national Building Performance Evaluation programme, and comprises 50 Passivhaus (PH) and 138 non-Passivhaus (NPH) dwellings, covering different built forms and construction systems. The difference between designed and measured values of air permeability (AP), external wall/roof thermal transmittance (U-value) and whole house heat loss were statistically analysed, along with a review of thermal imaging data to explain any discrepancies. The results showed that fabric thermal performance gap was widespread especially in terms of AP, although the magnitude of underperformance was much less in PH dwellings. While measured AP had good correlation with measured space heating energy for PH dwellings, there was no relationship between the two for NPH dwellings. The regression analysis indicated that for every 1 m 3 /h/m 2 reduction in designed air permeability, the gap increased by 0.8 m 3 /h/m 2 @50 Pa. Monte Carlo analysis showed that likelihood of AP gap was 78% in NPH dwellings designed to 5 m 3 /h/m 2 @50 Pa or lower. The study provides useful evidence for improving the fabric thermal performance of new housing through in-situ testing. [ABSTRACT FROM AUTHOR]

Automated compliance checking brings advantages to the built environment but, currently, there has been no meaningful adoption, despite the increasing maturity of asset information models. This paper addresses this by ascertaining the blockers/obstacles to adoption and develops a road-map to overcome them. This work has been conducted in the UK and a road-map has been produced to drive forward adoption. More specifically this paper has; assessed the current state of the art in the field and engaged with industry to examine the attitudes to the digitisation of regulatory compliance processes. The results showed that industry believes that adoption of automation was both feasible and desirable, with the caveat that human oversight be maintained. Our road-map's methodical list of steps was judged to have the potential to bring the construction industry to the verge of mass industrialisation of automated compliance checking by 2025. • Obstacles to automated compliance checking are technical, commercial and political. • Commercial and political obstacles viewed as most significant. • Wider Industry largely supports the concept of automated compliance checking. • A four-stage roadmap could bring mass adoption of automated compliance checking. [ABSTRACT FROM AUTHOR]

The rapid development of green buildings world widely has not delivered the anticipated energy related benefits because the real performance of green buildings is not as good as expected. This paper presents a building case study in China by applying a holistic approach which integrates system dynamics and energy performance simulation to evaluate the building performance gap and provide management strategies to minimize the performance gap. The case study in this paper is an office building located in Shanghai, which was awarded "Three Star" in Evaluation Standard for Green Buildings in China (GB/T 50378–2006). Several scenarios including six single management strategy scenarios and four multiple management strategy scenarios are carried out and in each scenario, building performance is analyzed qualitatively in terms of project quality (ranging from 0 to 1), and quantitatively in terms of energy use intensity (kWh/m2). The results of this case study are compared to another green office building located in the UK. The cross case mismatch between qualitative and quantitative results is due to four factors that performed better in reality that they were designed. It is demonstrated that multiple factors could help to increase building performance more than single factor especially when management cost was considered. The comparison of the two cases in China and the UK, shows that design factors should be treated in a more stringent way instead of referring values from local standard authorities only which could induce overdesign of the buildings. • This article integrates system dynamics with energy performance simulation. • This article tempts to quantify the effect of social factors on building performance gap. • This article documents well the developed framework and detailed application process to a case study in China. • This article provides a possible solution to help developers to improve actual building performance. [ABSTRACT FROM AUTHOR]

• New building development projects underperform often. • Underperformance leads to increased energy consumption and CO 2 emissions in building operation. • The paper links building project development and building operational performance. • Two simulation methods are combined in a multi methodology framework in the paper. • The paper explores the implications of project partner collaboration for operational building performance in the case of a recent building project. The "performance gap" in the United Kingdom construction industry is a persistent problem as new building development projects underperform more often than not. The "performance gap" is partially attributed to the number of stages involved in building project development and the coordination difficulties of partners with different incentives. The project outcome is important for energy consumption, carbon emissions and occupant well-being. Thus, it is important to study the project management process in terms of the standard time, cost and quality parameters, but also in terms of project partner incentives and coordination, and the subsequent energy performance and resultant indoor environmental conditions. A system dynamics model of project management processes is developed to explore the implications of partner coordination for building quality. The system dynamics model is coupled to a building performance simulation model to explore building energy consumption and Indoor Environmental Quality, and apply this on a recent building project case study. Results show that greater project partner alignment can reduce annual energy consumption up to 12% and CO 2 emissions up to 37%, with greater emphasis in the design stage of the project subject to resource availability. The trade-offs involved on value appropriation are considered and discussion of results points to possible ways for improvement. [ABSTRACT FROM AUTHOR]

This paper uses a socio-technical building performance evaluation (BPE) approach to assess the pre- and post- actual performance of two discrete deep low energy retrofits in the UK – a Victorian solid-wall house and modern 1990s cavity-wall house. A ‘low-energy first, then low-carbon’ approach was adopted in both cases, to achieve an 80% reduction in annual CO 2 emissions. Pre-retrofit, both houses had lower measured annual gas consumption as compared to predictions made by energy models, although the electricity consumption in the modern house was higher than modelled, due to occupancy pattern and occupant behaviour. Post-retrofit, it was found that the Victorian house achieved nearly 75% CO 2 reduction, while the modern house achieved only 57% CO 2 reduction over the baseline emissions. Key reasons were higher than expected air permeability rates, installation issues with micro-renewable systems, lack of proper commissioning, usability of controls, occupant preferences and behaviour. Despite the gap between expected and actual carbon emissions, occupant comfort and satisfaction was significantly improved across both retrofits. This evidence-based understanding of the process and outcomes of deep low carbon retrofits is vital not only for learning and innovation, but also for scaling-up deep retrofit programmes for meeting national and international carbon targets. [ABSTRACT FROM AUTHOR]

• Implementation of a model predictive control scheme for HVAC systems is presented. • The hardware/software solution is generalisable to most building management systems. • Cloud solutions can offer low-cost, scalable control in commercial buildings. • Economic MPC reduced energy usage by 1.7% compared to baseline control. • Building thermal performance strongly affects viability of MPC schemes. Many businesses are looking for ways to improve the energy and carbon usage of their buildings, particularly through enhanced data collection and control schemes. In this context, this paper presents a case study of a food-retail building in the UK, detailing the design, installation and cost of a generalisable model predictive control (MPC) framework for its Heating, Ventilation and Air Conditioning (HVAC) system. The hardware/software solution to collect relevant data, as well as the formulation of the MPC scheme, is presented. By utilising cloud-based microservices, this approach can be applied to all modern building management systems with little upfront capital, and an ongoing monthly cost as low as $6.39/month. The MPC scheme calculates the optimal temperature setpoint required for each Air-Handling Unit (AHU) to minimise its overall cost or carbon usage, while ensuring thermal comfort of occupants. Its performance is then compared to the existing legacy controller using a simulation of the building's thermal behaviour. When simulated across two months the MPC approach performed better and achieved the same thermal comfort for a lower overall cost. The economic optimisation resulted in an energy saving of 650 kWh, with an associated cost savings of $240 (an improvement of 1.7% compared to the baseline), while the carbon optimisation gave negligible CO 2 savings due to the inability of the building to shift heating to low-carbon periods. Findings from this study indicate the potential for improving building performance via MPC strategies, however the level of impact will depend on specific building attributes. [ABSTRACT FROM AUTHOR]

Stressed skin theory was first introduced in the 1960's and intensive development continued until the mid-1980's. This development was characterised by extensive research into the behaviour of low-rise portal frame structures clad with a single skin of profiled metal sheeting. The resulting state of the art was formalised in ECCS (1995). Since then, frames have become much taller and more slender while alternative cladding systems have proliferated. About 10 years ago, the construction industry in the UK was shaken by a small number of failures in the roofs of 'Big Sheds' clad with sandwich panels. Investigation by numbers of experts was inconclusive and non-disclosure orders (NDO's) were issued by the companies concerned. In the UK, the Standing Committee on Structural Safety (SCOSS) was informed of this and, after discussion with the Institution of Structural Engineers issued an Alert entitled 'Effects of scale' (SCOSS, 2018). This drew attention to the fact that validation of our current design rules has been largely based on years of satisfactory building performance. However, such evidence may not be indicative of satisfactory performance as structures increase in scale. In deference to the NDO's, a research program has been commenced based entirely on structural mechanics without making any direct reference to either forensic evidence from the sites of the failures or test results etc. that are not in the public domain. This is one of the papers arising from this research. It recognises significant deficiencies in the design procedures in the European Recommendations (ECCS, 1995) and the need for a full, non-linear, 3D numerical analysis of the complete clad structure. This, in turn, has resulted in the development of the 'component method' of analysis for structure cladding interaction problems that concentrates on the development of numerical models together with the performance of their 'components'. The main alternative cladding systems are considered in turn and their characteristics and potential failure modes identified. [Display omitted] • Stressed Skin Action of different cladding systems is investigated. • Single skin trapezoidal, sandwich panel, two-skin and cassette systems are assessed. • The existing state-of-the-art for each cladding system is established. • Simple nonlinear finite element models of each cladding system are generated. • The finite element models are validated against test results in the public domain. [ABSTRACT FROM AUTHOR]

Abstract: An archetypal simulation model of office building representing variability in UK office building stock by parameterising built form, construction elements, occupancy/usage and operational/control strategy has been developed thus enabling detailed energy performance simulation to be used for stock modelling and parametric studies. The paper discusses the building characteristics needed to be considered for energy performance simulation, their values, and how they can be used in parametric studies. These parameters include built forms, fabrics (including thermal mass and insulation positioning), glazing percentages and characteristics, daylight and solar control measures and activity and operational related parameters (heating and cooling set points, ventilation rate, occupancy density and metabolic rate, equipment and lighting gain). The default parameter values suggested for the archetypal simulation model reflect typical existing and currently proposed UK office building stock. An archetypal model, combined with parametric studies, can be used in assessing energy performance of building stock and evaluating adaptation/retrofitting strategies. [Copyright &y& Elsevier]

Abstract: The Low Carbon Futures project, funded by the Adaptation and Resilience in a Changing Climate (ARCC) Programme, has the objective of using the latest UK climate projections (UKCP’09) to assess overheating in a range of domestic and non-domestic buildings. As these climate projections are probabilistic in nature, and dynamic building simulation is being used by the project to assess building performance, the information produced is vast. To understand how to filter this data into a useable tool that can interact with current building practices, the project has commissioned a range of focus groups to obtain practitioner feedback. These focus groups provide guidance on how buildings are currently designed with respect to overheating but also how future overheating risk assessments, incorporating probabilistic climate projections, might be carried out. This paper describes the assimilation of all this research into a coherent building simulation methodology that could be used by building practitioners to assess future overheating risks of a range of buildings, and provide guidance for applying adaptation solutions to prevent defined comfort thresholds being exceeded. [Copyright &y& Elsevier]

Abstract: Recent activity in the development of future weather data for building performance simulation follows recognition of the limitations of traditional methods, which have been based on a stationary (observed) climate. In the UK, such developments have followed on from the availability of regional climate models as delivered in UKCIP02 and recently the probabilistic projections released under UKCP09. One major area of concern is the future performance and adaptability of buildings which employ exclusively passive or low-energy cooling systems. One such method which can be employed in an integral or retrofit situation is direct or indirect evaporative cooling. The effectiveness of evaporative cooling is most strongly influenced by the wet-bulb depression of the ambient air, hence is generally regarded as most suited to hot, dry climates. However, this technology has been shown to be effective in the UK, primarily in mixed-mode buildings or as a retrofit to industrial/commercial applications. Climate projections for the UK generally indicate an increase in the summer wet-bulb depression, suggesting an enhanced potential for the application of evaporative cooling. The paper illustrates this potential by an analysis of the probabilistic scenarios released under UKCP09, together with a detailed building/plant simulation of case study building located in the South-East of England. The results indicate a high probability that evaporative cooling will still be a viable low-energy technique in the 2050s. [Copyright &y& Elsevier]

Abstract: This study explores the uncertainties and sensitivities in the prediction of the thermal performance of buildings under climate change. This type of analysis is key to the assessment of the adaptability and resilience of buildings to changing climate conditions. The paper presents a comprehensive overview of the key methodological steps needed for a probabilistic prediction of building performance in the long term future (50 to 80years). The approach propagates uncertainties in climate change predictions as well as the uncertainties related to interventions in building fabric and systems. A case study focussing on an air-conditioned university building at the campus of the authors is presented in order to demonstrate the methodology. This employs the most recent probabilistic climate change projections for the United Kingdom (UKCP09 dataset) and takes into account facility management uncertainties when exploring uncertainties in the prediction of heating energy, cooling energy, and carbon emissions. [Copyright &y& Elsevier]

To reduce the substantial contribution of the built environment to energy consumption and carbon dioxide emissions, the new ‘Part L: Conservation of Fuel and Power’ of the Building Regulations for England and Wales came into force in April, 2006. As a result, the design of all new-build and refurbished buildings must comply with ‘Target Carbon Emissions Rates’. Apart from the purely practical implications of compliance, the new Part L has prompted interesting questions concerning procurement and the impact on design and construction teams. The so-called ‘traditional method’ of procurement presupposes that designs are, in theory, completed before contractor involvement. In contrast, Design-and-Build (of which there has been a marked increase) relies upon a certain amount of concurrency in design, procurement and construction. In the light of the new Part L requirements, this presents a risk, particularly in the case of environmentally sensitive buildings, where the necessary design iterations are at odds with the contractor''s time and cost incentives. These concerns have prompted the current investigation. Although the challenges relate to buildings as a whole, particular attention was paid to façades, as they represent an especially sensitive element. Data collection was by semi-structured interviews from a sample representing a selection of large construction companies, architectural practices and building performance consultants. The research framework was published in the proceedings of the 2007 Conference of the Association of Researchers in Construction Management where it was selected for discussion in an industry-wide forum, and the current paper reflects this response and develops the topic further. [Hamza N. Greenwood D. The impact of procurement routes on delivering energy conscious buildings. In: Boyd D. editor. Proceedings of Association of Researchers in Construction Management (ARCOM), Vol. 2; September 3–5 2007. p. 723–732, Belfast, Northern Ireland.] [1]. [Copyright &y& Elsevier]

Moisture is one of the major causes of damage to building systems, affecting the hygrothermal performance and durability of building systems. Surface treatment products are available in the market that can influence the hygric performance of masonry facades under water exposure. These are of a wide range of chemical compositions, and they claim to waterproof the masonry surfaces while not diminishing vapour transmissibility. This paper presents and discusses the findings from a series of benchtests carried out to measure hydrophobicity, water absorption and water vapour transmission following the relevant codes for an appraisal of the hygric behaviour change in brick masonry induced by waterproofing through three distinct phases of the life-cycle of moisture exposure, i.e. first contact with water, wetting and drying. To this end, 4 waterproofing products including silane/siloxane blend liquid and cream, and acrylic and stearate-based liquids were selected for testing, along with 3 brick types common in the 50s and 60s to be representative of the majority of the UK building stock. The findings show that the treatment products indeed enhance the surface hydrophobicity and reduce water absorption while allowing water vapour transmission to differing degrees: silane/siloxane blend cream overall was found the most effective throughout the moisture-exposure life-cycle, with an average of ~96% reduction in water absorption and 18% of increase in water vapour resistance in comparison to the untreated case, followed by the stearate-based liquid with 57% reduction in water absorption and 12% increase in water vapour resistance. The acrylic-based product demonstrated good performance in hydrophobicity and water vapour transmission tests, however led to a comparatively higher water absorption capacity than the other treatment products with only ~40% reduction in comparison to the base-case. Finally, silane/siloxane blend liquid was found to lead to the lowest contact angle, demonstrating a lower-than-others capacity to developing surface hydrophobicity, and led to 35% reduction in water absorption and 28% increase in water vapour resistance, making it the poorest product in the dataset to lead to watertight and vapour open systems under water exposure. Based on the test results it was also deemed beneficial to use masonry specimens to account for its composite nature, rather than using results obtained from brick and mortar separately to infer the wall response under exposure. • Performance characterisation of different waterproofing treatments on brick, mortar and masonry specimens. • 4 different waterproofing products, 3 brick types. • Hydrophobicity, liquid water absorption and water vapour transmission tests. • A lifecycle approach to detail performance at first contact with water as well as during wetting and drying. • An appraisal of the impact of curing time. • An appraisal of unintended consequences. [ABSTRACT FROM AUTHOR]

It is widely acknowledged that faced with diverse future impacts (including extreme weather events, economic instability, energy supply vulnerabilities and pandemics) buildings and communities' worldwide need to become increasingly resilient. The work presented in this paper investigates how Community Design and Decision Making (CDDM) processes can be enhanced using smart decision making techniques involving Building Performance Simulation (BPS). This work presents action research based on findings from a real-world case study project involving the design of a mixed-use zero carbon community centre, planned for the Findhorn Eco-Community, in Scotland, UK. Throughout the conceptual and early design stages the community played a crucial part in the decision-making process. BPS results coupled with the use of sensitivity analysis (SA) techniques incorporating resilience as a performance criterion contributed to establishing a multi-criteria evidence base from which to inform the CDDM process. Although not yet fully implemented in commercial simulation tools, the approaches used (e.g. uncertainty analysis, using resilience as a performance objective) proved to be invaluable in informing and facilitating the CDDM process. Overall an integrated two-way communication process (using BPS and uncertainty analysis for decision support) enabled the community to play an informed role in the design decision-making process. • Building simulation is poorly integrated in Community Design and Decision Making (CDDM). • Action research was used to assess building simulation in designing a zero-carbon community centre. • Resilience was evaluated as a design objective using smart decision making and building simulation. • Expert explanation of the 'how and why' of simulation facilitated acceptance of building simulation. • When used transparently building simulation showed great potential to enhance the CDDM process. [ABSTRACT FROM AUTHOR]

In this paper the findings from a long-term field study of the thermal performance of a circa 1950s dwelling are presented and discussed. The study aimed at evaluating the robustness of the QUB method in the field under UK climatic conditions. A series of 147 QUB tests were performed during the whole heating period (September 2016 – March 2017) in a detached house located in the University Park campus, University of Nottingham considering two distinct conditions: as-built and with increased airtightness. The QUB method was able to provide consistent and robust estimates of the Heat Transfer Coefficient (HTC) of the whole dwelling with approximately 80% of the results within ± 10% from the mean and more than 95% of the results within ± 15%. The need to treat heat losses occurring through the ground when assessing the thermal performance of buildings through experimental diagnostics methods was highlighted, especially in uninsulated concrete slab floors. The method devised to isolate the ground floor heat losses from the whole building losses resulted in reduced dispersion of the adjusted Heat Transfer Coefficient with a coefficient of variation of 5% and 98% of results within ± 10% from the mean. [ABSTRACT FROM AUTHOR]

The energy performance gap in buildings is a well-known phenomenon. However, its actual definition and extent is dependent on the baseline used for defining the gap. In this paper a calibration-based methodology is used to identify and validate the root causes of the performance gap. Following analysis of the performance of four case studies in the UK, from different building sectors, cross sectoral learnings that are applicable in the wider industry context are uncovered. Through the model calibration process and in the overall performance assessment, Indoor Environmental Quality (IEQ) parameters have been used to improve the robustness of validation of the calibrated models and to highlight the interrelationship of energy and IEQ. The study shows the importance of contractual accountability to minimise performance issues, building a case for having IEQ in energy performance contracts to manage the trade-offs of IEQ against energy performance that leads to unintended health consequences for the occupants. [ABSTRACT FROM AUTHOR]

This paper aims to study children's thermal comfort and related Adaptive Behaviours in UK primary schools. The study was carried out in 32 naturally-ventilated classrooms during Non-Heating (NH) and Heating (H) seasons. Alongside collecting environmental data, a self-reported questionnaire and an observation form were employed to record children's thermal comfort and adaptive behaviours. From eight primary schools, 805 children aged 9–11 were surveyed and 1390 questionnaires were collected. Children's Thermal Sensation Votes (TSVs), Thermal Preference Votes (TPVs) and adaptive behaviours were compared against temperature offset from comfort temperature by EN 15251 (T diff =T op -T C (CEN)). Results suggest that children's thermal comfort (T C (children)) is 1.9 K and 2.8 K lower than that for adults (T C (CEN)) during non-heating and heating seasons, respectively. Children have lower comfort temperature and higher sensitivity to temperature changes during heating seasons. This can be attributed to children's lower practice of personal behaviours and more consistent indoor conditions during heating seasons. The proportion of children engaged with personal behaviours is one-third lower during heating seasons. As indoor temperature goes above children's thermal comfort band, the proportion of children practising personal behaviours increases during non-heating seasons. Around 80% of window operation is carried out by teachers who have a higher comfort temperature than children. • Around 15% of children are overheated during both non-heating and heating seasons. • Children practice personal behaviours more than environmental behaviours. • The environmental behaviours are done based on teachers' thermal perception. • Only 16% of window operations are done based on children's thermal comfort. • TSV shifts one score by a temperature change of 11.1 °C (NH) and 7.7 °C (H). [ABSTRACT FROM AUTHOR]

Recently, retrofit of tower blocks has gained momentum particularly in the UK social housing sector due to the increasing rate of fuel poverty coupled with deteriorating indoor living conditions. However, the process of making improvements to the thermal performance of building envelopes can significantly impact on occupants' thermal comfort, increasing overheating risks with the changing climate and associated heat waves. The first phase of the study evaluated the building energy performance of a 1960s social housing tower block prototype in London, pre-retrofit, where the building simulation model was created and calibrated with monitored indoor data and occupants' interviews. The second research phase, the subject of this paper, uses the model to further investigate the impact of improved thermal insulation of the building envelope, based on U-values prescribed by the UK Building Regulations (Part L1B), on the potential risk of overheating. The study investigates the impact of retrofitting on occupants' thermal comfort and building energy performance in the current and future climate scenarios (2030, 2050 and 2080). Results confirm that improving the U-value of external walls will significantly reduce the heating energy use by 70% under future climate scenarios while the T o increases by 15–17% with U-value of 0.5 W/m2K and 0.3 W/m2K in comparison to the base case. The overall results indicate that the different occupancy patterns adopted in the simulation model have a significant impact on the predicted duration of overheating which will, in turn, have an impact on determining appropriate retrofit strategies to reduce overheating risks. • The overheating risk is not sufficiently addressed in the UK Building Regulations Approved Documents. • The study demonstrates the importance of real occupancy patterns in predicting overheating risks and heating energy demand. • Retrofitting 1960s tower blocks will have major impact on occupants' thermal comfort and building energy performance. • Improving the U-value of external walls significantly reduce the heating energy use by 70% under future climate scenarios. • Operative temperature increases by 15-17% with U-value of 0.5 and 0.3 W/m2K in comparison to the base case (0.9 W/m2K). [ABSTRACT FROM AUTHOR]