Research
Propertoasty Research — UK home energy efficiency data
TL;DR
- EPC Index — quarterly snapshot of UK council-area energy efficiency (17.8 M properties analysed).
- Affordability Index — trended year-on-year UK home energy data 2012–2026.
- Standalone deep-dives on Tower Hamlets, rural Wales, Burnley, postcode-level heating costs, and £/home savings.
- All findings reproducible via scripts/epc-bulk/ — source: GOV.UK EPC Register, OGL v3.0.
- Cite us with the page URL + 'Propertoasty Research, May 2026'. Press contact at /contact.
What we publish
Propertoasty Research is the open-data arm of the Propertoasty homeowner suitability service. We ingest the full GOV.UK EPC Register every month (5.4 GB, ~25 million certificates spanning 2008–present), run rollups by council area, postcode district, and property archetype, and publish findings that are useful to homeowners, journalists, and the retrofit industry.
Every page on this section cites methodology and the underlying queries — the EPC pipeline at scripts/epc-bulk/ is the reproducible workflow. Re-run quarterly = updated Index.
The series
EPC Index — UK home energy efficiency
Quarterly snapshot of UK council-area efficiency. Mean SAP score per LAD, year-over-year improver league table, national savings potential, national waste. The launch report is Q2 2026; refreshed quarterly thereafter.
Affordability Index — trended housing affordability
Year-on-year EPC snapshots across 13 UK regions — band shares, median heating cost, median floor area, mains-gas coverage. Tracks how UK housing affordability has shifted 2012 → 2026.
All entries
Affordability Index · 2026-05
UK Heat Pump & Solar Affordability Index 2026
Trended snapshot of UK home energy affordability across 5 lodgement years and 13 regions, built from the full GOV.UK EPC Register.
Read the reportEPC Index · 2026-05
Propertoasty EPC Index — Q2 2026
Five anchor insights on UK home energy efficiency: most + least efficient council areas, fastest improver, national savings potential, and national waste.
Read the reportEPC Index deep-dive · 2026-05
Tower Hamlets is the UK's most energy-efficient borough — and floor area is why
Why Tower Hamlets tops the UK's energy efficiency rankings with mean SAP 75.1 — the small-flat density story and what the league table doesn't tell you.
Read the reportEPC Index deep-dive · 2026-05
Mid-Wales homes waste £100 million a year on inefficient heating
Ceredigion, Gwynedd, Powys, Anglesey, Carmarthenshire and Pembrokeshire account for £101 M/yr in available household savings.
Read the reportEPC Index deep-dive · 2026-05
How Burnley gained 14 SAP points in a decade — the UK's biggest EPC improver
Burnley's mean EPC SAP score rose from 54.2 in 2014 to 68.2 in 2024 — the fastest improvement of any UK council area with comparable data.
Read the reportEPC Index deep-dive · 2026-05
£259 a year: the average UK home's energy efficiency saving — by council area
If every UK home cleared the recommendations on its current EPC, households would save £4.6 billion a year — an average of £259 each, rising to £534 in Ceredigion.
Read the reportEPC Index deep-dive · 2026-05
The UK's 5× heating-cost postcode lottery — from £225 to £1,180 a year
Median heating cost varies by a factor of 5× across UK postcode districts. Central-city flats pay £225/year; rural mid-Wales pays £1,180.
Read the report
Press + research enquiries
Citation form: “Propertoasty Research, [Month Year]” with a link to the specific page. For interviews, data requests, or pre-publication briefings, contact us via the contact page.
All findings are published under CC BY 4.0 for the analytical work. Underlying EPC source data is Open Government Licence v3.0 (© Crown copyright).
Sources
- GOV.UK — Find an Energy Performance Certificate (EPC Register) — accessed May 2026
- GOV.UK — EPC bulk download (technical documentation) — accessed May 2026
- Ofgem — Energy price cap — accessed May 2026
- DESNZ — Heat pump deployment statistics — accessed May 2026
EPC aggregate data contains public sector information licensed under the Open Government Licence v3.0 (© Crown copyright and database right).