EPC rating and sold prices in SA12 (Neath Port Talbot)
In postcode district SA12 (Neath Port Talbot), homes rated EPC C or better sold for 31% more per square metre than D–G homes (median £1,778 vs £1,360, 4,509 sales). Like for like — same size, type, build period and year — the difference is −0.3% (95% range −2.0% to +1.5%): the EPC band itself is not reflected in sale prices here. 1 of 4 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 85 m² against 88 m² for D–G; both groups are most often built in 1950–1966; 63% of C+ and 63% of D–G sales are detached or semi-detached houses.
| Comparing C+ with D–G homes… | Difference | 95% range |
|---|---|---|
| Raw gap per m² (medians) | +31% | — |
| Whole price, nothing held equal | +21.8% | +18.7% to +25.1% |
| Same floor area | +28.1% | +25.1% to +31.2% |
| + same property type | +23.5% | +20.9% to +26.2% |
| + same build period | +5.5% | +3.2% to +7.9% |
| + same year of sale | −0.3% | −2.0% to +1.5% |
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 SA12
| Sector | Sales | Raw gap | Like-for-like | 95% range |
|---|---|---|---|---|
| SA12 6 | 1,573 | +64% | +1.4% | −2.1% to +4.9% |
| SA12 7 | 854 | +8% | −0.3% | −2.7% to +2.1% |
| SA12 8 | 1,178 | +19% | +0.4% | −3.3% to +4.4% |
| SA12 9 | 904 | +38% | +5.2% ▲ | +1.0% to +9.5% |
▲ 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 SA12
| EPC band (last certificate before sale) | Sales | Median £ per m² |
|---|---|---|
| A | 12 | £3,233 |
| B | 248 | £2,532 |
| C | 1,372 | £1,690 |
| D | 2,167 | £1,422 |
| E | 599 | £1,181 |
| F | 93 | £1,094 |
| G | 18 | £1,128 |
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.