London EPC figures hide a striking home-efficiency divide, analysis of 2.6 million records finds
The capital has the lowest D-or-below share in the ten-region study, but unusually high Poor/Very Poor wall and window evidence.
An analysis of 2,639,163 searchable London EPC records reveals a sharp contrast between the capital’s overall EPC distribution and individual building-efficiency measures.
London has the lowest current D-or-below share among the ten regions at 44.01%. However, 56.00% of London records show Poor/Very Poor wall efficiency and 17.06% show Poor/Very Poor window efficiency.
London is also structurally different: 60.48% of records are Flats. When the loft calculation is restricted to House/Bungalow records with a known numerical loft depth, 46.99% are at or below 100 mm.
Islington records 55.34% on this applicable known-depth denominator, Kensington and Chelsea 54.66% and Camden 53.62%. Missing loft values are not treated as zero insulation.
Key figures
- Solar PV: Yes is 0.329% in London, the lowest regional share.
- Kensington and Chelsea and Westminster lead the qualifying triple-poor + D-or-below ranking.
- London has 405,277 D-or-below + potential A/B records.
About the research
The EPC Atlas UK Data Book 2026 Volume One v0.3 analyses 17,624,989 searchable records across ten England-and-Wales regional datasets. Scotland and Northern Ireland are outside the research corpus.
About EPC Atlas
EPC Atlas is a UK property and energy-performance data research and intelligence project designed to make large-scale EPC evidence searchable, comparable and easier to analyse at national, regional and local level.