Leeds Beckett University - City Campus,
Woodhouse Lane,
LS1 3HE
Lead Researcher: Professor David Glew
We also perform U-value measurement to help identify performance gaps in buildings and use air tightness testing and thermography to identify air leakage. We compare our measurements of building performance to models, including RdSAP and dynamic simulation modelling for new build and retrofit projects as well as evaluate overheating risks and assess the potential to deliver energy flexibility.
We also undertake elemental thermal modelling to evaluate thermal bridging heat loss and assess surface condensation risk in homes, as well as hygrothermal simulations to predict moisture accumulation in building fabric, which is essential for delivering a risk-based approach to building new low carbon buildings and delivering whole house retrofit.
Our new build and retrofit evaluation projects involve us making site observations, delivering toolbox talks, undertaking design reviews performing post occupancy evaluations with householders. We work with building designers, contactors, manufacturers, landlords and homeowners, and we are committed to share our knowledge to ensure theory can be embedded in practice so that zero carbon buildings can become a reality.
Professor Glew is Director of the Leeds Sustainability Institute (LSI) and Head of Sustainable Buildings.
Barnsley Metropolitan Borough Council have committed to lowering their energy and carbon footprint whilst simultaneously improving quality of living standards for their social housing tenants.
The Billingley View development seeks to achieve both aims, going beyond the minimum energy conservation requirements of the building regulations to pilot a new Barnsley low-carbon standard. This is achieved using simple strategies such as wider insulated wall cavities, minimal thermal bridging and an internal parge coat for airtightness. These details are all intended to avoid the need for any bespoke trade or material and are supplemented by low-energy technologies such as PV panels, battery storage and a heat pump.
The research utilised action research methods, with LSI researchers embedded throughout the project of design review, construction, post-completion testing and in-use monitoring. Overall, the standard appears to be achievable and effective, showing good resilience to onsite challenges. Potential issues were largely mitigated by senior site staff, highlighting the importance of an engaged site manager supported by a clerk of works who can assess overall quality to ensure consistency.
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Achieving air tightness in practice
This Department of Communities and Local Government-funded project considered the overall conclusions and key messages obtained through design assessments, construction observations, discussions with developers and pressurisation test results. The project analysed the airtightness performance of current UK housing, the implementation and impact of current and future legislation and identified potential areas for future work. Following an initial literature review, the project adopted an action research methodology that involved the research team working very closely with five developers to investigate the practical design and construction issues that arise in making improvements to the airtightness of speculatively built mainstream housing. Two construction types were represented in the project, masonry cavity and steel frame. The project highlighted a number of issues that need to be considered when constructing dwellings to meet a particular airtightness target. Suggesting that certain construction types appear to be intrinsically more airtight than others, complexity of the design can have a significant effect on airtightness, certain approaches to improving airtightness are likely to be both more successful and more robust than others and that achieving consistently high levels of airtightness in dwellings may prove difficult within existing design and construction cultures.
Research outputs
Challenging the equity of UK Energy Price Caps
In 2017, the British Government imposed a cap on prepayment energy prices in an attempt to combat fuel poverty. The maximum amounts allowed in the price caps were based on national averages, which can ignore some of the finer detail in the data. In this work, we used smart-meter data to see if any demographics are not receiving the full benefit of the price caps. The findings suggest that many economy 7 customers are not behaving typically, and may find themselves still struggling under the current price caps.
Research outputs
Standardising how to measure the efficiency of buildings
Based upon our international reputation associated with undertaking electric coheating tests, Professor David Johnston was invited to become an expert member of the British Standards Institution B/540/9 and CEN Technical Committee 89 Working Group 13 Task Group 5. As part of his CEN Working Group role, he has been working with European colleagues to develop a new European (CEN) standard based upon the Whole House Heat Loss Test Method (Coheating) developed at Leeds Beckett University. The new standard is entitled 'Thermal insulation – Construction products, building elements and structures – In-situ measurement of thermal performance – Testing of completed buildings Part 1: Data Collection'.
Research outputs
For more information about this project please contact us.
The gold standard for measuring the Heat Transfer Coefficient in buildings
The electric 'co heating' test, which is in the process of being developed into an international CEN standard and has been used by other institutions (both in the UK and abroad) as the reference test for assessing the aggregate performance of the building fabric in both new and existing dwellings. The electric coheating test has also been used to validate other building fabric thermal performance methodologies and is forming the basis of future research into validating building fabric thermal performance through the use of smart meter data. A quasi-steady state test method undertaken on an unoccupied dwelling to quantify the Heat Transfer Coefficient (HTC) of the dwelling in W/K. Currently in the process of being converted into a CEN standard.
Research outputs
Read more about H21Cavity party wall thermal bypass investigations
This work was funded by Eurisol, the UK Mineral Wool Manufacturers Association. This project followed on from the Stamford Brook field trial, which identified significant heat losses via party wall cavities in terraced and semi-detached masonry houses, and proposed various techniques to eliminate or minimise the effect. The purpose of this study was to extend the work carried out at Stamford Brook, and help in the development of practical low-cost solutions to mitigate of heat loss via party wall cavities.
Research outputs
Early investigations into the effectiveness of retrofits
The overall objective of this project was to define a coherent conceptual and analytical framework within which the technical requirements for the next three reviews of Part L can be debated and decided. The key objective of the project was to chart a possible course specifically for fabric performance out to 2013 and later. The L1 project was carried out for the ODPM Building Regulations Division under the Building Operational Performance Framework by the FMNectar consortium.
Research outputs
Identifying errors in EPCs
Funding was provided by the Economic and Social Research Council via the Consumer Data Research Centre. Energy Performance Certificates (EPCs) give people an idea of how energy efficient their homes are, but EPCs are notoriously unreliable and full of errors. This project identifies EPCs which are likely incorrect allowing them to be removed from any analysis. The project found that a large number (up to 62%) of EPCs contain at least one major error, calling into question how useful they are as a measure of energy efficiency in their current form. Furthermore, the errors found in each region of the UK varies considerably, with London containing the most.
Research outputs
Reliable building energy performance characterisation based on full-scale dynamic measurement
After building a strong reputation in building performance characterisation, the Centre for the Build Environment (CeBE) at Leeds Beckett University were invited to participate in the International Energy Agency Annex 58. The ultimate goal of the Annex is to develop the necessary knowledge, tools and networks to achieve reliable in situ dynamic testing and data analysis methods that can be used to characterise the actual energy performance of building components and whole buildings.
Research outputs
Investigating the potential for flexibility to solve energy problems of the future
Leeds Sustainability Institute's building performance group are taking a lead on the International Energy Institutes Annex 67 project, Energy Flexible Buildings project, with more than 20 participants from across Europe and further afield. The project has commenced its preparatory year, with substantial input from our university, looking into how buildings can contribute and interact with energy networks.
Research outputs
For more information about this project please contact us.
Identifying the causes of damp to protect vulnerable tenants and inform council interventions
As part of the project investigating the condition and damp issues in Leeds City Council-owned homes, Leeds Sustainability Institute at Leeds Beckett University were commissioned to undertake a series of quantitative and qualitative research exercises. These were: airtightness measurement of dwellings, thermographic survey of dwellings, occupant interviews, and analysis of in-use internal environment data. Overall, the airtightness of dwellings in the research sample is not a major concern when considering their age and material condition. The key consideration, however, is that the values presented are for uncontrolled air movement aggregated across the whole dwelling. It is likely that air exchange is not occurring in a consistent way, with some areas potentially over-ventilating (e.g. windows, gaps and cracks) and some under-ventilating (e.g. wet rooms). It is for this reason that it is necessary to undertake a thermographic survey alongside the airtightness test when the dwelling is depressurised. The thermal surveys identified several commonly occurring issues with the building fabric, which may contribute to the formation of damp and mould. One barrier to tenants taking preventative action was a lack of capability due to faulty or non-existent mechanical ventilation systems. Although aware of risk, occupants reported very little guidance for damp prevention, suggesting a lack of knowledge towards both the cause and prevention of damp. Damp prevention guidance may therefore be effective in reducing damp occurrence.
Research outputs
For more information about this project please contact us.
Local councils spend a substantial amount each year resolving issues arising from damp and disrepair in their social housing stock. To understand the causes of these issues, the LSI undertook a series of quantitative and qualitative research exercises in collaboration with NPS and Leeds City Council. These tests included: airtightness measurement of dwellings, thermographic surveys of dwellings, occupant interviews and analysis of in-use internal environment data. This series of tests were performed across a representative sample of 31 dwellings taken from a wider estate where issues with damp were higher than average.
The sample was selected to include dwellings both with reported damp issues and with no reported issues, so that data may support the identification and disaggregation of likely risk factors contributing to moisture related issues.
The project was instrumental in identifying commonly occurring fabric issues, including missing insulation, thermal bridging, faulty seals, and penetrating moisture. Engagement with the occupants also highlighted common behaviours that led to an enhanced risk of moisture issues, such as under ventilation and indoor clothes drying. Importantly, the research also explored the rationale behind such behaviours and the occupant perspectives on risk, responsibility and awareness when considering the links between moisture, damp, and mould. The findings were used by Leeds City Council to improve their strategy for retrofit and damp mitigation, including providing additional guidance to occupants on managing moisture in the home.
Identifying energy efficiency improvements in supermarkets
Energy use and management in supermarkets represents a challenge as well as an opportunity. Improvements have the potential to benefit companies and consumers, and to contribute to the achievement of UK carbon reduction targets. This research project has the aim of improving energy efficiency in supermarkets using data visualisation tools. Funding was provided by Innovate and partners were: ASDA, who provided the data and case studies, Cybula, who developed the software, REMS and the Leeds Sustainability Institute (LSI), based at Leeds Beckett University. The project identified that it is recommended that visualisation tools should only be used in stores where there is high confidence around the quality and quantity of available data and a data capture pro forma has been developed to inform this. Shop floor area is conventionally the preferred method of normalising energy data to rank store performance. This was found to be acceptable and other minor variables were discovered to be relatively unimportant. However, using volume to normalise gas and HVAC energy use, and using chilled floor area when normalising refrigeration energy provided the best normalisation. Two approaches were used to predict a store’s ‘normal’ performance. The first simply used data to determine the mathematical correlation between energy use and energy demand. This produced a somewhat useful model for gas use and refrigeration energy use that could be incorporated into a visualisation tool, though HVAC energy use displayed much weaker correlation. The second approach used calibrated simplified dynamic simulation models to create baseline models of stores to compare stores as well as assessing changes in energy caused by varying inputs such as same ceiling heights.
Research outputs
For more information about this project please contact us.
Nationwide BPE investigations into Low Carbon Homes
In 2011, the Technology Strategy Board (now Innovate UK) launched the £8million Building Performance Evaluation (BPE) Programme. An overarching aim of the BPE programme was to assemble comparable data and knowledge about a large number of buildings to enable analysis across the body of case study information, leading to generic findings conclusions and learning for the sector as a whole. As part of this Programme, the Centre for the Built Environment (CeBE) were successful in securing over £500,000 of external funding to undertake six post construction and early occupation studies (25% of all of the domestic projects awarded under the Technology Strategy Board BPE Programme) and two in-use performance and post occupancy evaluation studies. Additionally, all participants involved in the wider BPEP were required to adhere to standardised BPE practices based on the Leeds Beckett University Coheating Text Protocol.
Research outputs
Evaluating airtightness in BISF and solid brick social housing
Wakefield District Housing (WDH) commissioned the Leeds Sustainability Institute (LSI) at Leeds Beckett University to undertake pressurisation tests and thermographic surveys on 20 semi-detached dwellings. The results showed that there was no noticeable improvement in the airtightness of dwellings that had EWI compared to those without EWI in either BISF or solid walled dwellings. A larger sample size of BISF homes without EWI and both solid walled properties with and without EWI would be needed to assess if this finding was statistically significant. CO2 decay analysis was used in an attempt to validate the blower door results, however, the results were inconclusive due to a low sample size and uncontrolled conditions due to occupant activity. Improving air tightness is not the main function of EWI and this has been sustained by our findings. The results confirm that the fabric performance benefit of EWI is restricted almost exclusively to improving wall U-values, i.e. reducing heat loss through the fabric, not affecting heat loss through uncontrolled ventilation in the dwellings.
Research outputs
For more information about this project please contact us.
In 2019, the City of York Council (CYC) declared a climate emergency in response to the increasing impact of climate change.
The CYC Net Zero Fund Renewable Heating Upgrade project represents a significant investment in achieving carbon emission reductions, and aims to achieve this through the replacement of existing electric storage heaters in two independent living developments with efficient Air Source Heat Pumps (ASHPs) and Photovoltaic (PV) solar panels with battery storage.
The Leeds Sustainability Institute has been appointed to evaluate the project to determine whether the aims of reducing energy consumption and improving the living conditions of residents have been achieved. This evaluation utilises a range of research methods, including detailed monitoring of energy use and environmental conditions, thermographic surveys, resident interviews and survey questionnaires.
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There is a wealth of research exploring retrofit performance immediately following construction or installation.
However, there is more limited data on how retrofit insulation performance changes over a longer period with performance assumed to be constant over the service life of the insulation. The aim of this project was to establish the existing evidence on the impact of retrofit degradation over time, and what it means for insulation performance.
The project included a comprehensive review of academic and grey literature to collate published information, an evaluation of existing datasets to establish their potential to generate new insights, and a package of social science activities with expert stakeholders to develop recommendations for future research.
Taken together, the research identified substantial gaps in knowledge that require addressing prior to any future policy designed to accommodate retrofit deterioration. Data is required on UK building materials that have been naturally aged, with consideration for a variety of insulation degradation mechanisms, including poor quality install, accidental disturbance, and material breakdown. Specifically, data should be captured to represent suboptimal conditions. This should also assess a range of housing archetypes and geographical spread present in the UK, to determine whether 'one size fits all' estimations of performance decline are appropriate.
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This project was funded by Innovate UK as part of the their Net Zero Heat Programme: Rapid assessment of building fabric performance.
The aim of the project was to develop, verify, and optimise a rapid, novel, low-cost hand-held technology for locating and quantifying air leakage in the built environment. Leeds Sustainability Institute's (LSI's) role in this project was to comparatively evaluate the performance of the novel hand-held device.
This involved undertaking a series of comparative tests with existing technologies on a range of holes of known size within a controlled environment, as well on leaks in partially-controlled and uncontrolled, real-world environments. The tests found that the novel device is a useful instrument to augment existing airtightness testing methodologies and can identify, quantify and rank areas of air leakage. They also demonstrated the instrument's potential to enable rapid assessment of building fabric performance in a greater range of environments and situations, for example, by identify key leakage areas when pressurisation is impossible due to incomplete building envelopes.
This project was part-funded at the University of Leeds by the Engineering and Physical Sciences Research Council (EPSRC) under its Impact Acceleration Award (IAA) programme.
The aim of this project was to measure the airtightness and identify the main air leakage points attributable to nine dwellings that form part of the Low Impact Living Affordable Community (LILAC) development, located in the West of Leeds, West Yorkshire. Two separate commercially available devices were used to measure airtightness: an Energy Conservatory Minneapolis Blower Door and a Low Pressure Pulse (LPP) 2.0 Test unit by Build Test Solutions. A wide range of mean air permeability was observed for both the blower door and LPP tests, with no clear difference in the results observed for different dwelling forms. In addition, a number of the LPP test results were lower than the corresponding blower door tests, even when the higher level of uncertainty associated with the tests was accounted for. Air leakage detection was also undertaken using infra-red thermography. This identified a number of common areas of air leakage across the dwellings.
Assessing the airtightness of holiday homes
The aim of this project was to quantify the air permeability and identify the main areas of air leakage associated with a number of prototype holiday home hire fleet models that were being produced by Atlas Leisure Homes. It is estimated that in the UK, 200,000 residents live in park and holiday homes all year round, the majority of which are elderly and on low incomes. As these homes are often thermally inefficient and leaky, these residents are some of the most susceptible in society to fuel poverty. The results identified a number of common air leakage areas within the test caravans, suggesting that there may be a fundamental industry-wide issue associated with the way in which these homes are constructed which needs to be addressed. In addition, the results also indicate that utilising the air permeability metric within Sherman’s ratio (Q50/20) to approximate the average annual air infiltration rate, introduces a bias into holiday homes, due to their high surface to volume ratio. This bias is not unique to holiday homes and will be equally applicable to other building types with similar surface to volume ratios.
Research outputs
Assessing the fabric thermal performance of holiday homes
The aim of this project was to undertake a number of in situ measurements of the thermal performance and airtightness of a small number of new 2016 model fleet hire holiday homes. The in situ measurements were undertaken to enable the heat loss attributable to each holiday home to be disaggregated into its constituent components. All of these measurements were undertaken for Bourne Leisure Limited, one of the largest holiday home park operators in the UK. These measurements were undertaken to enable Bourne Leisure Limited to determine the optimum levels of insulation (and U-values) that should be specified for the main external elements of their fleet hire holiday homes. This project presents the results obtained from undertaking detailed building fabric thermal performance tests on a small sample of new holiday homes. The results of these tests indicate that although a building fabric thermal performance ‘performance gap’ exists in all of the holiday homes tested, the results suggest that the ‘gap’ is much smaller than that documented for new build UK housing and may be more of a consequence of the way in which the design intent of these homes has been determined, i.e. a ‘prediction gap’, rather than a ‘performance gap’ between assumed and realised in situ performance. These results could be used by industry to develop more appropriate prediction tools that are relevant to holiday homes.
Research outputs
Condensation modelling of theoretical and real-world details
The project, ‘Impacts of Improvements to Part L and Robust Construction Details (RCD) on Part C’ was funded by the Department of Communities and Local Government and consisted of a fieldwork element, undertaken by Leeds Metropolitan University, and a modelling element carried out by the Bartlett School of Graduate Studies, University College London. The fieldwork consisted of the analysis of design material and site surveys from 16 housing developments constructed to Part L 2002 and adopting the Robust Construction Detail route to compliance. The results of the analysis were used to enable condensation modelling that took into account not only the guidance of robust details but also the way in which construction details were actually designed and, perhaps more importantly, constructed. The modelling element of the project sought to identify the extent to which the ‘as built’ details give rise to a significantly increased condensation risk as compared to the relevant ‘standard’ robust construction details, as defined in the guidance.
Research outputs
BPE of sustainable housing development
This project set out to provide a robust approach to the evaluation and monitoring of the Elm Tree Mews sustainable housing development in York. The development is being undertaken by the Joseph Rowntree Housing Trust, supported by the Joseph Rowntree Foundation and is intended to address the issues involved in creating low carbon, sustainable housing. It is anticipated that the lessons learned will be fed back to the industry at large. The research project consisted of a retrospective evaluation of the design and construction process, performance measurements of the dwellings as constructed (compared with design expectations) and the monitoring of energy and other performance characteristics of the dwellings in use.
Research outputs
Embedding flood protection into regulations
The recent instances of severe flooding in the UK together with predictions on future flooding from the OST Foresight project have given rise to significant interest by Government, financial institutions, insurers, the construction industry and the general public for the need to improve the local flood protection of buildings. This has been driven by the requirement to protect the health and safety of the individuals living and working in affected properties, as well as the need to reduce the economic cost of flooding. The location of developments and buildings and their height above ground and local water levels are planning issues covered in Planning Policy Guidance which encourages development away from areas at risk of flooding. However, there is a level of residual risk for developments in marginal areas and in areas that become at risk as a result of climate change. Accordingly, it is essential that new developments are constructed appropriately to minimise the risk of flooding to occupants and users of buildings.
The flood protection industry, regulators and other stakeholders in the management of flooding are concerned about the lack of detailed knowledge on the resistance and resilience to flood waters of building materials, construction methods and building designs, and also the effective use of flood protection measures. There is a lack of both field performance data and also science-based information on how buildings, walls and floors behave in flood conditions. The use of inappropriate building materials could result in poor performance and in the extreme could affect the structural performance of buildings and the health of occupants. Current guidance on improving the flood resistance of new and extended buildings has, in the main, been developed on the basis of expert opinion and there is now a clear need to enhance our knowledge through scientific analysis. The aim of this project was to identify how existing and new knowledge could be incorporated into the Building Regulations and to produce guidance for new dwellings consistent with Government initiatives and common construction practices. A wide variety of individuals and organisations were consulted and contributed to the final outputs. The role of Leeds Metropolitan University in the project was to provide support to the other team members in terms of specialist knowledge of construction materials, construction forms, construction technology and building regulations.
Research outputs
Low carbon homes; prototype testing
Hill Housing Ltd and Leeds Beckett University employed a Knowledge Transfer Partnership Associate to assist in the evaluation of prototype low energy homes in Cambridge. The associate, supported by Leeds Sustainability Staff undertook design reviews, building performance testing, in-use monitoring, post occupancy evaluation of the home and identified many successes and identified improvements that could be taken forward into the main multi-home scheme. The homes themselves outperformed all the homes the LSI have previously tested; the performance gap that was measured was within the margin of error of the test, meaning that this may be the first home built in the UK, that has been tested, without any measurable performance gap at all.
Research outputs
UK Passive House Conference, October 2019, Mainstreaming Passivhaus by 2030, Manchester, UK, - Chris Gorse speaker profile
Knowledge exchange for low carbon construction
The LowCarb4Real project has been carried out by an interdisciplinary partnership of Leeds Metropolitan University, University College London, Leeds University and the Good Homes Alliance, with funding from the UrbanBuzz Programme. This partnership has been supported by an advisory group of key stakeholders that included representatives from CLG, Taylor Wimpey, Redrow Homes, the Zero Carbon Hub, Construction Skills, National Trust, the Housing Corporation, the Home Builders Federation and the Sustainable Building Association (AECB).
The LowCarb4Real project was designed to develop the knowledge necessary to make low and zero carbon housing a reality, where it matters, 'on the ground'. It sought to set up a knowledge exchange programme based on the lessons from the Stamford Brook housing field trial and the experience of those developers seeking to build beyond current building regulations. The Stamford Brook field trial was an action research project funded by the Department for Communities and Local Government (CLG) and based around a 700 house development undertaken by Bryant Homes and Redrow Homes, on land owned by the National Trust. The six-year field trial sought to assess, in a comprehensive way, the issues involved in improving the carbon performance of mainstream house building. It has generated an unprecedented amount of learning related to airtightness, envelope integrity and systems performance, at all levels including building physics, dwelling design, site management, workforce training and procurement systems. Given the challenging regulatory targets proposed by government aimed at zero carbon new housing within 10 years, it is crucial that the learning from field trials such as Stamford Brook is captured, refined, contextualised and embedded as thoroughly as possible within the house building industry. The project also seeks to provide a model for industry-based research and knowledge exchange.
Research outputs
Implementing advanced energy standards for housing
Stamford Brook is a development of around 700 cavity masonry dwellings that was being constructed on part of the National Trust’s Dunham Massey Estate near Altrincham in Cheshire. Construction on the site commenced in 2004 and continued until around 2009/2010. The development was carried out under a partnership agreement between the land owner, the National Trust, and the two developers Redrow and Bryant Homes. The development partners were also participating in a 'Partners in Innovation' (PII) project with the Centre for the Built Environment at Leeds Metropolitan University that has investigated various aspects of the design and construction processes. The Stamford Brook PII project is a unique record of the achievements, successes, failures, problems and solutions that can occur during the implementation of an advanced energy standard on a large-scale housing development. Using participatory action research methodologies, the research project team has followed the progress of the development from initial discussions on the energy standard and environmental standard, through the detailed design process, observation of construction of the dwellings, performance testing of completed buildings and monitoring of occupied houses.
Research outputs
Comprehensive evaluation of an enhanced energy performance home
This project examined whether an energy performance standard similar to the 1995 Swedish regulations could reduce space heating and associated CO2 emissions in new UK dwellings by 80% compared with those built to the then current standards, while guaranteeing affordable warmth and dramatically reducing fuel poverty in new housing. Such a standard could in principle form the basis for future revisions to the UK Building. Its implementation would face a number of barriers. The construction industry would need to be convinced that the standard was workable, that costs were proportionate to the objectives and that the risk of building failures and defects was acceptable.
The St Nicholas Court Field Trial was set up in 1999, with funding from the Joseph Rowntree Foundation, the Housing Corporation and from the DETR under the Partners in Innovation Programme, to address these issues. The project sought to comprehensively evaluate the impact of an enhanced energy performance standard in the context of a development of 18, timber-framed houses built at St Nicholas Court for York Housing Association by Wates Construction Ltd.
Research outputs
Building performance evaluation for new build social housing
Wakefield District Housing (WDH) and Leeds Beckett University (LBU) were successful in securing funding for a Knowledge Transfer Partnership. The project focused on evaluating the performance of new build social sector housing.
The application of Dynamic Thermal Simulation models to WDH new build housing demonstrates the potential to evaluate a wide range of construction options at design stage. The DTS analysis work presented here also shows how calibration of models against measured and metered data can improve their accuracy and usefulness in considering alternative scenarios. The potential changes in construction and their impact on energy performance (and utility bills) has been quantified in this report. The DTS analysis also illustrates the potential risk of overheating in low-energy dwellings but also that this can be mitigated through simple design and operational changes, such as internal blinds or increased window opening angles.
As a whole, this in-use monitoring data demonstrates that the new build dwellings currently owned by WDH Ltd are relatively well performing. The in-use monitoring data does however also illustrate the wide range of user behaviour in the context of thermal comfort and also, some scope to offer advice to tenants on how small changes in behaviour may help them to reduce utility costs without adversely affecting their thermal comfort.
Developing an innovative solution for eaves insulation
Thermal bridging calculations that were undertaken to assess the thermal performance of the ARC T-Barrier product. The calculations were undertaken by the Centre for the Built Environment within the Leeds Sustainability Institute at Leeds Metropolitan University as part of a collaborative project with the product’s developer ARC Building Solutions Limited. The project was supported by a Technology Strategy Board Innovation Voucher.
Designs for the party wall/external wall abutment junction for masonry and timber-frame constructions were thermally modelled to compare the thermal bridging attributes of junctions with the ARC T-Barrier product installed against junctions with a more conventional cavity barrier product that is also manufactured by the company. Comparisons were also made with the published linear thermal transmittance (Ψ-value) for the corresponding Accredited Construction Details (ACD). Potential options for improving the ARC T-Barrier product for use in timber-frame applications were explored.
Research outputs
For more information about this project please contact us.
Read more about H21Investigating the efficiency of ground source heat pumps
A collaborative 3-year research project funded by EPSRC in partnership with E.ON. The academic partners were: UCL (lead partners), Leeds Metropolitan University, Loughborough University, De Montford University, Kings College London, Cardiff University and the University of Greenwich. CCC uses the methodology of Action Research to engage users in the design of control systems which will reduce energy use (and therefore carbon emissions) in dwellings, whilst retaining or enhancing levels of comfort for the occupants. The aim was to achieve a 20% reduction in energy use through working more effectively with existing technologies and building fabrics, via the development of control systems which are both convenient to use and appropriate to the needs of users with a variety of lifestyles. The control systems were designed and tested in a way that complies with utilities’ CERT-2 obligations, and the project also developed design, installation and maintenance guidelines which will enable a wider application of important principles identified.
Research outputs
A product to complement EWI and combat condensation risk
Mould growth and surface condensation are problems for many dwellings, and the retrofitting of insulation can increase the risk of these occurring. This is especially the case for historical solid wall properties receiving external wall insulation (EWI), which often have architectural details at the roof eaves that cause discontinuities in the insulation and so can result in excessive thermal bridging. This paper presents the results of an investigation into retrofitted solid wall properties where modelling is used to investigate the problem and effectiveness of insulated coving products which are designed to reducing thermal bridging. Thermal modelling is undertaken to establish the optimum design to reduce risk. The insulated coving was found to be effective in reducing thermal bridging in all the scenarios investigated and to reduce moisture risks occurring in some solid walls situations.
Research outputs
Evaluation of Heat Pump Performance
Harrogate Borough Council has placed itself in the forefront of sustainable development of existing social housing stock by installing Ground Source Heat Pump technology in around 80 properties, with plans for further installations in the future. Ground Source Heat Pumps extract heat at relatively low temperatures from an external ground loop or borehole, and transfer this heat to water in a heating system, raising its temperature sufficiently to provide both space heating and domestic hot water. The system can be supplemented by a small amount of electrical resistance heating to cover any shortfall and to raise domestic hot water temperatures to high levels for short periods, e.g. during pasteurization cycles. Some monitoring of heat pump operation and performance has already taken place and some (limited) contextual information (building type, occupancy, maintenance etc.) is also available. This data has been gathered by Harrogate Borough Council as part of normal operations, without, as yet, any attempt at a systematic analysis of heat pump performance across the Borough. This project aims to systematize existing data, using the conclusions drawn to inform the scope and methodology of future data collection. As far as is practicable at this stage it will assess the energy cost and CO2 savings achieved by the systems, and will develop in-depth case studies of a small number of selected installations via collection of additional data.
Research Outputs
Investigating the impact of heating system deaerators
In the UK, approximately 16% of the energy use can be attributed to domestic wet central heating systems. Government financial support and advances in technology have led to boilers becoming more efficient and a range of technologies are now available that claim to be able to improve the efficiency of domestic wet central heating systems. One such low-cost technology is a passive deaerator.
This article presents the results obtained from installing a passive deaerator on the closed loop of a gas-fired wet central heating system, under controlled conditions in the Salford Energy House. The results indicate that although marginally less heat output was required from the boiler when the passive deaerator was operating, these savings are more or less out weighted by the boiler short cycling more frequently. Consequently, the overall reduction is gas consumption achieved by utilising the passive deaerator device is only of the order of 0.5%; this scale of savings may just be a consequence of measurement noise. The implications are that although a marginal benefit may be attributed to these products, if short cycling takes place, then these savings may become insignificant. Practical application: This article describes a test method that has been used to quantify the energy savings that could be achieved by installing a passive deaerator on the closed loop of a wet central heating system. Although the results indicate that the energy savings associated with using such a device are likely to be marginal, the test method described could be used to test a range of other devices that claim to improve the performance of domestic wet central heating systems, to directly compare before and after performance.
Research outputs
This National Energy Action funded project is at the forefront of healthy homes research.
The LSI collaboration with Biomedical researchers in LBU School of Health is trailing a methodology for sampling mould in 18 homes in South Yorkshire, which have been identified as having historic mould issues. Following baseline measurements, new ventilation solutions and other remediation strategies to remove mould, and the risk of mould recurring, are being tested. LBU will return to the homes following the interventions to assess the success of these strategies and evaluate the mould measurement methodology.
Empty homes represent a missed opportunity for the provision of housing to those in need of quality accommodation.
Additionally, when a building is left vacant for an extended period, this often carries an enhanced risk of deterioration caused by disrepair and neglect. The Empty Homes Retrofit project is an initiative led by North Yorkshire Council to bring currently vacant properties back into use, whilst also improving the thermal performance via retrofit thermal upgrade. Three homes were identified for the project, with a variety of construction types, locations, and starting condition.
The Leeds Sustainability Institute were appointed to evaluate the homes before and after retrofit and provide a comparison between the pre- and post-retrofit building condition. To do this, a suite of building performance evaluation tools was used to assess the building fabric and airtightness. Notably, the fabric testing occurred during warmer seasonal periods, trialling the efficacy of tests such as the overnight QUB test where external conditions were suboptimal.
The project observed significant improvements in the fabric performance of all test dwellings and ultimately succeeded in bringing three previously disused homes into the North Yorkshire Council housing stock. Although challenged by the warmer external conditions, QUB tests were found to produce statistically robust HTC values for the buildings, indicating their potential for warmer-weather fabric performance evaluation.
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The QUB-ED project aimed to provide validation of QUB a rapid, novel, low-cost technology for measuring whole house heat loss (Heat transfer Coefficient (HTC)).
LBU undertook an extensive long term testing programme conducting hundreds of QUB measurements on two test cells and a historic grade 2 listed building. The results showed how changing test conditions can impact the accuracy of measurements and how the test setup could be altered to mitigate these impacts.
LBU also engaged with industry, conducting interviews and focus groups with 54 professionals to understand how measurement methods such as QUB could be usefully deployed within the retrofit sector. This revealed there are multiple potential use cases for such methods such as providing quality assurance, education and in communicating the benefits of retrofit. However, several barriers were identified relating to commercial constraints, practicalities and possible industry resistance. The findings suggest integration in retrofit policy is necessary for the successful deployment of measurements.
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Leeds Beckett University were one of seven UK universities, along with the Energy Saving Trust, that participated in a five year project funded by the UKRI Engineering and Physical Sciences Research Council (EPSRC) to develop a Smart Energy Research Lab (SERL). The project was led by University College London (UCL) and the aim was to provide access to half-hourly energy data and other relevant contextual data for the research community. As part of this project, the Leeds sustainability Institute (LSI) within Leeds Beckett University investigated the potential of using smart meter data to derive a new performance metric relating to the 'heat up time lag' of domestic space heating systems. Further details regarding the SERL project can be obtained from the SERL website.
This involved undertaking a series of comparative tests with existing technologies on a range of holes of known size within a controlled environment, as well on leaks in partially-controlled and uncontrolled, real-world environments.
The tests found that the novel device is a useful instrument to augment existing airtightness testing methodologies and can identify, quantify and rank areas of air leakage. They also demonstrated the instrument’s potential to enable rapid assessment of building fabric performance in a greater range of environments and situations, for example, by identify key leakage areas when pressurisation is impossible due to incomplete building envelopes.
The Temple Avenue Project, funded by the Joseph Rowntree Housing Trust and conducted by the Centre for the Built Environment at Leeds Beckett University, outlined the initial evaluation of the design, construction and performance of two prototype low carbon dwellings and helped establish the extent to which an existing 1930s masonry house could be renovated so as to achieve a level of performance commensurate with the advanced energy and carbon standards of the prototype new dwellings.
The two prototype dwellings contained some technological innovation and were constructed in 2009 as part of the development of house type designs for the proposed Derwenthorpe low carbon housing scheme on the eastern edge of York. One prototype was constructed using thin-joint masonry construction and another using a structural insulated panel (SIPs) build system. The concurrent renovation works to an adjacent existing dwelling explored the impact of two standards of renovation, one reflecting the standard fabric measures that were considered to be cost effective and one reflecting the more challenging requirements of an 80% emissions reduction and incurring greater capital costs.
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This project delivered at-scale retrofit to 198 properties in the Wakefield and District Housing (now VICO Homes) stock.
The homes received external wall insulation (EWI) and loft insulation top-ups. Additionally, the homes received innovative 'Internet of Things' (IoT) improvements, which included a smart thermostat, a smart positive input ventilation (PIV) system, and a smart air brick for under-floor ventilation.
To evaluate the success of the retrofit, the LSI conducted fabric performance tests, thermal modelling, in-use monitoring, and over 100 hours of interviews with tenants, housing association staff and retrofit contractors.
Overall, the project was successful in achieving many of its objectives, including an apparent decrease in energy and carbon consumption, an increase in occupant thermal comfort and well-being, and a positive sentiment at an organisational level. Where less positive elements of the retrofit were found during the research, such as issues during the retrofit process and inconsistent communication between stakeholder groups, these have been applied to produce a set of recommendations for use in future retrofit schemes of this nature.
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