Pictured from the left are research team members Saim Memon, Becky Mallaband, Keyur Vadodaria, Professor Dennis Loveday, Professor Phil Eames and Vicky Haines
Project CALEBRE (Consumer Appealing Low Energy technologies for Building REtrofitting) has been a five year project co-ordinated by Dennis Loveday, Professor of Building Physics in the School of Civil and Building Engineering. The project focused on the challenges presented by ‘hard to heat, hard to treat’ properties. These are predominantly the 8.3 million solid wall houses which make up 34% of UK housing stock. “From the outset, the approach was to put householders’ perspectives and their lifestyles at the heart of our thinking around the technical developments and investigations that we undertook that could ultimately lead to refurbishment solutions that appeal to customers.” Professor Loveday explains. “We investigated a suite of techniques and technologies spanning the current, medium and longer term informed by householder perspectives and supported where appropriate by business case modelling. The methods we employed included laboratory investigations, field trials and modelling, together with use engagement techniques.” The CALEBRE project focused on three key areas – reducing heat demand, the efficient supply of heat and householder behaviour – with separate teams from six universities working on nine distinct but related projects across these areas. Researchers at Loughborough led projects which focused on householders’ appetite for improvement and their tolerance for change, on energy efficiency refurbishments and the technology of vacuum glazing. Loughborough academics were also a key part of the team looking at airtightness improvements and ventilation systems in domestic refurbishment.
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the research & enterprise view
Householder attitudes To investigate attitudes, barriers and motivators to refurbishment the Loughborough team, led by Vicky Haines, Head of User Centred Design Research Group, carried out semi-structured interviews of households in owner occupied ‘hard to treat’ solid wall houses in the East Midlands. The aim was to uncover their reasons for carrying out past home improvements with a view to understanding the barriers and the motivations towards future refurbishments. The data highlighted a range of interrelated and sometimes rather intangible barriers to making home improvements to older properties. The primary barriers are information and awareness, hassle and cost. Findings indicated that people’s motivation to carry out refurbishment was not so much the need to save energy bur rather the desire to improve comfort and the need to repair.
Commenting on her research Vicky said: “We found that refurbishing people’s homes in an acceptable way is a complex process. Householders present a range of social and technical barriers to easy retrofit. By taking these into consideration it is possible to better design retrofit policies and practices that appeal to householders and align with their lifestyles.”
Vacuum glazing Window energy performance is seen as crucial for improving the energy performance of buildings. It is estimated that up to 90 million tonnes of CO2 emissions could be saved annually by 2020 if all Europe’s buildings were fitted with double-glazed insulating glass. This saving could be significantly increased if a higher performance glazing system was widely available. Vacuum glazing is such a system and leading the Project CALEBRE investigations in this area was Loughborough’s
Phil Eames, Professor of Renewable Energy and Director of the Centre for Renewable Energy Systems Technology (CREST). The work was undertaken with Dr Trevor Hyde from the University of Ulster.
“With the introduction of the Government’s Green Deal for promoting large-scale domestic energy efficiency refurbishment the substantial work of Project CALEBRE is extremely timely.”
A range of vacuum glazings were fabricated using different techniques. They were extensively tested under laboratory conditions to assess thermal performance and durability. They were then installed in a test house where they were assessed again. They were tested a third time having been removed from the house. A range of edge seal materials and processes were also investigated and trialled.
“Our research has shown that high performance vacuum glazing has the potential to greatly reduce heat loss through the building envelope with a consequential reduction in carbon emissions,” says Professor Eames. “Further investigations are however required if commercialisation on a large scale is to be realised and we need to assess the attitude of planners and other statutory bodies to the wide scale deployment of this technology,” he adds.
Airtightness Existing homes in the UK have varying levels of airtightness. Improving it is important as leakage of air is a significant source of heat loss from homes. The Project CALEBRE team – Mark Gillott from Nottingham and Loughborough’s Professor Loveday and Keyur Vadodaria – sought to investigate how easy or challenging it is to achieve good airtightness when refurbishing a house. They measured the airtightness of a test house completely unrefurbished. They then carried out five successive stages of
refurbishment including conventional measures such as double glazing and then more advanced techniques such as the installation of a whole house mechanical ventilation and heat recovery system. Professor Loveday explains their findings: “Each set of applied retrofit measures contributed to an improvement in airtightness but with variable success. We found it is possible to refurbish a house for energy efficiency and it is possible to achieve high levels of airtightness through attention to detail and quality of workmanship. Energy saving can be achieved from properly installed modern mechanical ventilation and heat recovery systems.”
Members of the Loughborough team also contributed to work looking at the impact on energy and carbon savings of the order of retrofit of domestic energy efficiency measures. Overall the Project CALEBRE team have generated many academic papers and this work is ongoing. They have contributed significantly to the growing body of knowledge that can support the UK Government and industry in achieving reduced energy demand by the UK housing stock. The team is undertaking additional research on the projects already initiated and they aim to bring to commercial success some of the technologies investigated. Professor Loveday concludes: “With the introduction of the Government’s Green Deal for promoting large-scale domestic energy efficiency refurbishment the substantial work of Project CALEBRE is extremely timely.”
Project CALEBRE was an E.ON/ Research Councils UK funded research project undertaken by a team of six leading UK universities and led by Loughborough. The full Loughborough team comprised Professor Dennis Loveday, Professor Phil Eames, Dr Vicky Haines, Keyur Vadodaria, Becky Mallaband and Saim Memon. The other CALEBRE project partners were the Universities of Oxford, Warwick, Ulster, Nottingham and Heriot Watt University. Further information about all the CALEBRE research projects is available at www.calebre.org.uk
the research & enterprise view
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