A new study from the University of Cambridge suggests that insulation improvements within UK homes have a limited impact on their long-term gas consumption.

The study, which assessed the gas use of more than 55,000 dwellings in England and Wales for five years before and after insulation was installed, found that:

• Cavity wall insulation led to an average 7% drop in gas consumption in the first year, falling to 2.7% in the second. By year four, average energy savings were negligible.

• Loft insulation resulted in an initial 4% drop in gas consumption. This fell to 1.8% after one year and was negligible by year two. In homes with conservatories, average improvements were negligible after a year.

The findings suggest that energy-efficiency improvements are often cancelled-out by behaviour changes such as turning up the heating or opening windows in stuffy rooms. The researchers also noted that energy efficiency retrofits are often implemented alongside home improvements that increase energy consumption, such as adding an extension (previous research suggests that an extension typically increases household energy consumption by 16% ).