EPC rating and sold prices in CF40 (Rhondda Cynon Taf)
In postcode district CF40 (Rhondda Cynon Taf), homes rated EPC C or better sold for 29% more per square metre than D–G homes (median £1,403 vs £1,091, 2,793 sales). Like for like — same size, type, build period and year — homes rated C or better sold for 4.7% more (95% range +1.5% to +7.9%). 1 of 2 sectors with enough sales show a difference distinguishable from zero. Data: HM Land Registry to 30 September 2026, EPC register.
From the raw gap to like-for-like
The homes are not alike: C+ homes here have a median floor area of 82 m² against 82 m² for D–G; both groups are most often built before 1900; 27% of C+ and 13% of D–G sales are detached or semi-detached houses.
| Comparing C+ with D–G homes… | Difference | 95% range |
|---|---|---|
| Raw gap per m² (medians) | +29% | — |
| Whole price, nothing held equal | +30.8% | +24.9% to +36.9% |
| Same floor area | +27.4% | +22.6% to +32.4% |
| + same property type | +21.0% | +16.9% to +25.4% |
| + same build period | +14.8% | +10.6% to +19.3% |
| + same year of sale | +4.7% | +1.5% to +7.9% |
The first row compares median prices per m²; the second compares whole prices; each later row adds one more thing that must be equal, ending with the like-for-like premium (regression of log price; build period from the certificate, 12 bands). The raw gap per m² and the whole-price gap differ because C+ and D–G homes differ in size.
Postcode sectors in CF40
| Sector | Sales | Raw gap | Like-for-like | 95% range |
|---|---|---|---|---|
| CF40 1 | 1,152 | +39% | +4.6% | −0.7% to +10.2% |
| CF40 2 | 1,641 | +20% | +4.8% ▲ | +0.9% to +8.9% |
▲ green: premium distinguishable from zero; ▼ red: discount; plain: no measurable difference. Small areas have fewer sales, so their 95% ranges are wider.
Sold prices by EPC band in CF40
| EPC band (last certificate before sale) | Sales | Median £ per m² |
|---|---|---|
| A | 1 | too few |
| B | 23 | £1,683 |
| C | 461 | £1,386 |
| D | 1,493 | £1,167 |
| E | 657 | £987 |
| F | 117 | £857 |
| G | 41 | £789 |
A median is shown when a band has at least 10 sales.
How this is calculated
- Every standard sale (HM Land Registry Price Paid, category A) since January 2015 is matched to the latest energy certificate of the same address (postcode + house number or name + flat) lodged from 10 years before to 3 months after the sale; sales with no certificate or an ambiguous match are left out. Across England and Wales 92% of sales match.
- Price per m² uses the certificate's total floor area (15–1,000 m²).
- Like-for-like premium: regression of the log of price on “C or better”, log floor area, property type, the certificate's build period and the year of sale. The 95% range shows how precise the estimate is; when it includes zero, the data cannot tell the premium apart from none.
Caveats
- The band is the one on the certificate before the sale; certificates are a median 0.8 years old at the sale, but a quarter are over 4 years old and some homes were improved since.
- Condition, garden, parking, views and the exact position within the sector are not known; a premium could hide in them, or they could hide one.
- Individual sales and addresses are not shown.