Insulation only provides short-term reduction in household gas consumption

Insulating the lofts and cavity walls of existing UK housing stock only reduces gas consumption for the first year or two, with all energy savings vanishing by the fourth year after a retrofit, according to research from policy experts at the University of Cambridge.

Insulating. Photo: Erik Mclean/Unsplash

The latest study is the first to track in detail household gas use across England and Wales for at least five years both before and after insulation installation.

Researchers analysed gas consumption patterns of more than 55,000 dwellings over twelve years (2005-2017), and found that cavity wall insulation led to an average 7% drop in gas during the first year.

This shrank to 2.7% in the second, and by the fourth year, any energy savings were negligible.

Loft insulation was half as effective as cavity wall, with an initial fall in gas consumption of around 4% on average, dropping to 1.8% after one year and becoming insignificant by the second year.

For households with conservatories, any gains in energy efficiency disappeared after the first year.

The findings suggests that when it comes to home insulation there may be a significant 'rebound effect': any savings through energy efficiency get cancelled out by a steady increase in energy use.

Researchers behind the study say it is extremely difficult to identify specific causes of the 'rebound effect' they found, but behaviours such as turning up the heating, opening windows in stuffy rooms or building extensions may all contribute.

They argue that good insulation is vital, but any drive to insulate UK homes should be combined with investment in heat pump installation and campaigns to encourage behaviour change.

To capture the overall effect of insulating homes, the researchers accounted for various factors, including the age and size of buildings, the weather and gas prices.

However, they did find that gas price influenced energy use – so the soaring cost of gas may mean greater energy reductions from insulation now than during the study period.

The research also found household gas consumption fluctuated less after both loft and cavity wall insulation.

Anadon and her Cambridge co-author Dr Cristina Penasco say that insulating old and draughty housing across the UK is a vital step, but argue that not encouraging homeowners to “fully degasify heating” while going through the disruption of a retrofit is a missed opportunity.

Heat pumps, which extract warmth from outside to heat internal radiators, are highly efficient and negate the need for gas boilers.

Recent research suggests the UK lags behind many other European countries on heat pump sales, and the UK Committee on Climate Change has also highlighted the need to speed up heat pump deployment. (University of Cambridge)

YOU MAY ALSO LIKE

London Underground polluted with metallic particles small enough to enter human bloodstream

The London Underground is polluted with ultrafine metallic particles small enough to end up in the human bloodstream, according to University of Cambridge researchers. These particles are so small that they are likely being underestimated in surveys of pollution in the world’s oldest metro system.

Crop waste cattle feed solution ‘averts toxic fires’

Farm residue can be converted into nutritious cattle feed, say researchers.

Rio city bans use of loud fireworks

The City Council of Rio de Janeiro on Tuesday (Dec. 6) approved definitively the bill banning the manufacture, sale, and use of fireworks in the city.

Photos suggest rhino horns have shrunk over past century, likely due to hunting

By scrutinising over a century’s worth of photos, University of Cambridge researchers have made the first ever measurements that show rhinoceros horns have gradually decreased in size over time.

Large grazing mammals offset climate effects

A study conducted over a 16-year period in India’s Himalayan region confirms what scientists have always believed — that large, grazing mammals play a vital role in stabilising soil carbon and mitigating the effects of climate change.

Sea-level rise ‘may cross two metres by 2100’

The Asian Development Bank (ADB) recommends raising to two metres, instead of the existing one metre, the imaginary waterline demarcation for projects in the Asia Pacific region to improve the resilience of structures against rising sea levels.