Data sources

The property details we pre-fill are keyed to your home's Unique Property Reference Number (UPRN) and brought together on HomePortfolio, a UK property-intelligence platform of 29.5 million-plus records built on the sources below. Nothing here is observed about you - it is public record.

Drives your EPC band, floor area, fabric quality and modelled heating cost, and the per-area EPC-band distributions on our cooling guides.

Source: Energy Performance of Buildings Data (England & Wales), used under its published open-data terms.

Construction era, property type and local planning-approval rates come from the national planning data platform and the EPC register. Local planning authority boundaries, which we use to attribute each application to the right council by location rather than by matching authority names, come from the same platform.

Source: planning.data.gov.uk.

Contains public sector information licensed under the Open Government Licence v3.0.

Every council in the UK keeps a statutory planning register: a permanent public record of the applications it receives and the decisions it makes. Our cooling-specific approval rates, refusal grounds and condition profiles are computed from the decided applications on those registers, filtered to air conditioning, condensers and heat pumps. When we show you a local precedent, it is a real application a real council decided.

We publish the application reference, a shortened description of what was proposed, the decision and its date, and the council that made it. We do not publish applicant, agent or case-officer names, or full addresses. We publish decided applications only, never live ones. Every entry links back to the council's own register, which is the authoritative record - if it disagrees with us, it is right and we are wrong.

Source: the statutory planning registers of UK local planning authorities, kept under section 69 of the Town and Country Planning Act 1990 and article 40 of the Town and Country Planning (Development Management Procedure) (England) Order 2015, aggregated via PlanIt.

Aggregate planning figures contain public sector information licensed under the Open Government Licence v3.0. Individual register entries are published as statutory public-register information; we publish them because homeowners cannot otherwise see what their council actually decides, and we withhold every field that would identify a person. If an entry concerns your property and you would like it removed, email [email protected].

Local price context for cost estimates.

Source: HM Land Registry Price Paid Data.

Contains HM Land Registry data © Crown copyright and database right 2026. This data is licensed under the Open Government Licence v3.0.

Whether a home is in a conservation area or is (or is near) a listed building - which changes the planning route for an outdoor unit. Conservation-area status is a point-in-polygon result; listed-building status uses building outlines where they exist (post-2011 listings) and point-proximity otherwise.

We refresh listed-building data weekly and conservation-area data monthly. Because the conservation-area layer is publicly known to be incomplete for some local authorities, we never present a coverage gap as “not in a conservation area” - we say so plainly and tell you to confirm with your local planning authority. We are not Historic England and do not speak for it; we report what the public records show, as of the date shown, and always point you to your council for the final position.

Sources: Historic England - National Heritage List for England and planning.data.gov.uk conservation-area & listed-building datasets.

© Historic England 2026. Contains Ordnance Survey data © Crown copyright and database right 2026. This information is licensed under the Open Government Licence v3.0.

The overheating model is grounded in CIBSE TM59 and Building Regulations Part O; grant rules follow the gov.uk Boiler Upgrade Scheme and accreditation follows MCS. These are the standards the model encodes; the methodology sets out exactly how.