Data Sources
The official datasets, registers and authorities we rely on to research, verify and update the information on this site.
We want every factual claim on RetroFit Leeds to be checkable. This page lists the primary sources we draw on, what we use each one for, and the broad cadence at which we re-check them. Where we cite something on a guide or service page, we link out to the original source so you can verify it yourself.
UK Government & Regulators
Used for scheme rules, grant amounts, eligibility criteria, and statutory standards.
- Department for Energy Security and Net Zero (DESNZ) — scheme rules and grant amounts for ECO4, the Boiler Upgrade Scheme (BUS), the Great British Insulation Scheme (GBIS), and the Warm Homes Plan.
- Ofgem — administrator of the Energy Company Obligation (ECO4) and Smart Export Guarantee (SEG); tariff registers.
- GOV.UK — statutory guidance, scheme application pages, and standards references.
- Energy Performance Certificate open data — EPC distribution analysis by area, ward and postcode.
- Office for National Statistics — housing stock context, household income and tenure data for West Yorkshire.
- BSI Group — PAS 2030 and PAS 2035 retrofit standards.
Accreditation Registers
Used to verify the accreditations listed against each provider in our directory. Each provider record is cross-checked against the relevant register before being published or re-verified.
- TrustMark — government-endorsed quality scheme for home improvement work.
- MCS Certified — Microgeneration Certification Scheme installer register.
- FENSA — window and door installation registration.
- Gas Safe Register — statutory register of gas engineers in Great Britain.
- NICEIC — electrical installer certification.
- NAPIT — competent person scheme for electrical, plumbing, heating and renewables.
- RECC — Renewable Energy Consumer Code.
- HIES — consumer protection scheme for home energy installations.
- Which? Trusted Traders — independently assessed trader endorsement.
Local Authorities
Used for local scheme details, eligibility flexibility (ECO4 Flex), council-run retrofit programmes, and local planning notes.
Independent Bodies & Research
- Energy Saving Trust — consumer guidance, savings estimates, and retrofit advice.
- National Energy Action (NEA) — fuel poverty research.
- Cavity Insulation Guarantee Agency (CIGA) — cavity wall insulation guarantees.
- National Insulation Association — industry guidance.
Datasets we publish
We also publish a small number of aggregated datasets derived from the open sources above. These are licensed under the Open Government Licence v3 (the licence of the underlying data) and are free to view, reference and link to.
- EPC band distribution across West Yorkshire — aggregated EPC ratings by local authority and postcode area for Leeds, Bradford, Wakefield, Kirklees and Calderdale. Refreshed quarterly from the official DESNZ EPC register.
How we keep this current
Government scheme details (grant amounts, eligibility, application routes) are re-checked against official publications when changes are announced and on a routine review cycle. Provider accreditations are checked against the relevant register when each provider is added and on subsequent re-verification — the Listing verified date on each provider page records the last check.
If you spot information on this site that is out of date or doesn’t match its source, please tell us — see our corrections page.