# Homes are getting warmer

> Two in five certificates reached band C in 2011. Seven in ten do now.

- Category: Environment
- Cadence: monthly
- Status: Published on a monthly cadence.
- Dataset key: `epc-over-time`
- Source: [MHCLG](https://get-energy-performance-data.communities.gov.uk/)
- Licence: Open Government Licence v3.0 — [terms](https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/)
- Canonical page: [https://londongraph.com/g/homes-are-getting-warmer](https://londongraph.com/g/homes-are-getting-warmer)
- Machine-readable record: [https://londongraph.com/data/homes-are-getting-warmer](https://londongraph.com/data/homes-are-getting-warmer)

## Methodology

Share of London certificates rated C or better, by the year the certificate was lodged. Read this as the efficiency of what was being certified that year rather than of London's housing as a whole — a rising line reflects tightening building standards, retrofits done before sale, and the mix of properties changing hands, and cannot separate them. The current year runs to the most recent complete day rather than to December.

## Visualisations

- [Trend](https://londongraph.com/g/homes-are-getting-warmer): Two in five certificates reached band C in 2011. Seven in ten do now.
- [Change](https://londongraph.com/g/homes-are-getting-warmer?view=change): Show the change from each preceding published period.

## Citation guidance

Attribute the original publisher named above and identify LondonGraph as the visualisation and methodology layer. Do not describe live values as a historical census, and do not present placeholder values as observations.