Underfloor heating study reveals huge benefits in older homes
Last week, the government published its long-awaited Clean Growth strategy, which looked at various ways of reducing carbon emissions across the life and economy of the UK. This included homes, which account for 13 per cent of total emissions.
While much of the focus was, and has been, on ensuring modern homes are built to high standards of environmental quality, the issue of retrofitting existing buildings is a crucial one if Britain is to meet its targets. Around two-thirds of the buildings that will be standing in 50 years are already in existence.
It is often assumed that the older a building is, the harder it is to insulate. However, new research by University College London (UCL) and the University of Sheffield suggests that many homes built before the Second World War have underfloor cavities that, if insulated, could see eat loss reduced by as much as 92 per cent.
The study was carried out by Dr Sofie Pelsmakers, lecturer in environmental design at the University of Sheffield, alongside Dr Cliff Elwell of the UCL Energy Institute. They tested the effects of two types of insulation in a Victorian house with an underfloor cavity. One used wood fibre insulation and the other beads, with tests being carried out at 27 different points across the floor surface to provide comprehensive readings.
Dr Pelsmakers explained: "When we analysed the results of the tests, it showed a 65 per cent reduction in heat loss for the wood-fibre insulation, and a 92 per cent reduction for bead insulation. Our research suggests that there could be massive potential for cost savings in the average property."
Titled 'Suspended timber ground floors: Heat loss reduction potential of insulation interventions', the study noted that as many as ten million homes in the UK have timber floors suspended above a solid concrete base, with a narrow air pocket in between. The paper will be published later this month in the trade magazine Energy and Buildings.
When it comes to actually fitting such material, the authors estimate that it would cost £200 for a skilled DIY practitioner to install it. Of course, many people would not feel confident in doing this and would be best off hiring a professional fitter to ensure the job is done well.
Indeed, Dr Pelsmakers noted that the wood-fibre bricks do need to be packed tightly to ensure there are no gaps in the insulation, otherwise its effectiveness will be diminished. However, she also added the caveat that once the area is sealed up, moisture can be trapped. However, she said further research will "hopefully" find solutions to this soon.
Summarising the benefits of this kind of insulation, she said: "We’ve already seen how simple steps like improving insulation and reducing draughts can prove economical.
"In the future, ground floor insulation may provide another effective means to reduce energy consumption."
All that may be music to the government's ears, as improving the insulation of some of Britain's older housing stock may ease a major headache.
Speaking to the BBC Radio 4 Today Programme last week before the publication of the Clean Growth Strategy, energy minister Claire Perry said a combination of "carrots and sticks" could be used to encourage people fit insulation in their homes and punish those who do not. She said this could include variable stamp duty rates linked to home energy performance.
In view of the latest research, it could be that as this policy area is developed, new incentives may be focused on underfloor heating in some older homes.