A lack of experienced retrofit practitioners and difficulty in sourcing suitable products are preventing the UK from retrofitting homes at the rate needed to achieve its carbon reduction targets, concludes a new study.

The report by the Institute for Sustainability and UCL Energy Institute analyses eight projects from the Technology Strategy Board's £17 million 'Retrofit for the Future' (R4tF) programme.

Among its findings are that the supply chains needed to support large-scale retrofit are currently underdeveloped and more work is required to create capacity. There is both a lack of experienced retrofit practitioners and difficulty in sourcing the products and technologies required. Both areas represent significant opportunities for the industry and would be aided by further trials at whole-street and neighbourhood scale that build on the experience of the R4tf programme, says the report.

Eight projects consisting of 10 homes were selected from the 25 retrofit projects funded by the R4tF programme in the London area. House types in the sample included semi-detached, detached and terraced properties built between the late 19th and late 20th centuries.

Institute for Sustainability chief executive, Ian Short said: "This initial analysis of the 'Retrofit for the Future' programme is an important step forward in understanding how national carbon reduction targets can be met in a way that creates value and improves quality of life for householders. The findings identify a number of areas where focus and investment could help scale up domestic retrofit to the levels needed. These include supply chain capacity, occupant engagement and retrofit project management practices."

The full findings will be officially launched on 6 December 2012 [the report is now available], however, key findings include:

• Successful retrofits in the sample appear roughly to halve carbon emissions, supported higher internal temperature and levels of comfort, and generated high or very high occupant satisfaction levels.
• Better integrated project teams were more likely to be successful -  they engaged and communicated better with occupants, implemented better design solutions, managed occupant expectations of disruption more effectively, and produced better handover information. They were also better at supporting and building in learning to the process for the project team and its members.
• High levels of “problem retrofits” are very likely to impact adversely on the occupant experience and produce low satisfaction levels. This could prejudice the roll-out of domestic retrofit nationally.
• The costs of deep retrofit are, at present, significantly more than the likely limits on expenditure under the Green Deal, however, costs will reduce significantly as the scale of retrofit delivery ramps up, stimulating new economies and up-skilling in supply chains.  Payback measurement does not consider other values such as improved quality of life for occupants, value added to the property and better health outcomes. It is also important to note that optimal cost of the retrofit  was not the primary goal of the project which was set up to encourage innovative, collaborative 'whole house' design delivering deep, 80% carbon reductions far beyond current UK practice.
• The supply chains needed to support large-scale retrofit are currently underdeveloped and more work is required to create capacity.

The UK has set the target of an 80% reduction in carbon emissions from buildings by 2050. Housing in the UK accounts for 27% of carbon emissions and at least 60% of the houses in use in 2050 have already been built.

Access the full report.

Listen to the 2degrees webinar 'The Route to Zero Carbon Homes' or 'Whole house low energy refurbishments'.