dwellify

What is Dwellify?

Dwellify brings together open UK government datasets to give you a clear picture of any residential property — energy performance, sale history, estimated value, land boundaries, and neighbourhood context — all in one place.

It's a personal project built to make publicly available property data more accessible and useful. All data comes from official government sources published under the Open Government Licence.

Coverage

Dwellify currently covers 4,976,541 residential properties across 496,797 postcodes in England, Wales and Scotland. Coverage is limited to properties that have both an Energy Performance Certificate and at least one recorded sale in the Land Registry Price Paid dataset.

Properties that have never been sold (e.g. long-held or council-owned) or that lack an EPC will not appear.

How Valuations Work

Estimated property values are calculated using one of three methods, shown by the confidence indicator next to each valuation:

High confidence — HPI-indexed, sold within 5 years

The actual sale price is adjusted to today's value using the UK House Price Index for the property's type and location. Most reliable for recent sales.

Medium confidence — HPI-indexed, sold over 5 years ago

Same method, but older sales are less reliable as the property may have been improved or deteriorated since the last transaction.

Low confidence — machine learning model

For properties with no sale history, a CatBoost gradient-boosted model predicts value based on floor area, property type, location, energy efficiency, and other features. Typical accuracy is within 9% of actual sale prices.

All valuations are estimates and should not be used for financial decisions. See our disclaimer for details.

Condition Score

The condition indicator compares a property's actual sale price to what the model predicts for a similar property. If a property sold for more than expected, it may suggest better-than-average condition, renovations, or desirable features not captured in the data. A negative premium may suggest the opposite — or simply that the buyer got a good deal.

This is a statistical indicator, not a building survey. Many factors beyond physical condition can explain why a property sold above or below its predicted value.

Data Sources

Dwellify is powered entirely by open government data: Energy Performance Certificates, Land Registry Price Paid Data, UK House Price Index, INSPIRE Index Polygons, Ordnance Survey Open UPRN, and OS Open Data. Full details and licence information are on the data sources page.

Contact

Questions, feedback, or spotted something wrong? Get in touch at [email protected].