The average energy efficiency of UK homes has steadily improved over time, but the rate of improvement has slowed since 2014. The latest comparable data shows that homes in Northern Ireland had the highest average energy efficiency rating, followed by Scotland and England, with the lowest average rating in Wales. This briefing looks at data on energy efficiency levels across the nations of the UK, variations by different types of properties and households, insulation
measures and government funded/mandated energy efficiency schemes.