The UK will not be able to meet 2050 climate targets unless every home is retrofitted, according to a new report from the Institution of Engineering and Technology (IET) and Nottingham Trent University.

Their definition of retrofitting includes adding solar panels or other renewable energy sources, improving insulation and ventilation, and implementing sustainable heating systems.

The report states that energy used in homes accounts for about 20% of UK greenhouse gas emission three-quarters of that comes from heating and hot water.

It adds that 80% of the homes people will inhabit in 2050 have already been built, meaning it is not possible to rely on new builds alone to meet legal energy-saving targets set in the 2008 Climate Change Act.

Rick Hartwig, IET Built Environment lead, said: ‘If we are to meet the 2050 targets of the Climate Change Act, then all housing in the UK must have zero carbon emissions from space and water heating, and space cooling.

‘New and innovative products will always assist in reducing costs and improving energy performance, but sufficient work has already been done in research and pilot studies, to show that massively reducing the carbon emissions and energy requirements of current housing is achievable and needs to be done. Retrofitting has other benefits too, making cold homes warmer, healthier and reducing bills.

‘There is considerable practical experience in financing deep retrofit projects, managing them, and engaging with the householders. We need to build on that experience to create a national retrofit programme to deliver our 2050 goals. This will not only help drive demand but allow greater scale to cut the costs per property.

With local authority and housing association homes accounting for 17% of all homes in the UK, Mr Hartwig believes retrofitting these is the ‘logical place to start’ as it will scale up demand for retrofitting and drive down costs.

According to the report, current barriers to the development of a national programme include a lack of customer demand, ineffective policies, high costs, and a lack of investment.

Professor Marjan Sarshar, Nottingham Trent University, added: ‘Achieving retrofits to 2050 standards is technically challenging and currently too expensive. New knowledge-based supply chains, advanced manufacturing techniques and better business models are necessary to reduce costs.

‘Ten early demonstrators have already been achieved in Nottingham, through an EU project called Remourban. Joint action from government and Registered Social Landlords (RSLs) will allow scaling up of these early experiences at a national level.’

Read the full report here.