EPC rating and sold prices in SA11 (Neath Port Talbot)
In postcode district SA11 (Neath Port Talbot), homes rated EPC C or better sold for 36% more per square metre than D–G homes (median £1,744 vs £1,281, 5,086 sales). Like for like — same size, type, build period and year — homes rated C or better sold for 3.8% more (95% range +1.8% to +6.0%). 2 of 5 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; the most common build period is 2012 onwards for C+ and 1900–1929 for D–G; 64% of C+ and 49% of D–G sales are detached or semi-detached houses.
| Comparing C+ with D–G homes… | Difference | 95% range |
|---|---|---|
| Raw gap per m² (medians) | +36% | — |
| Whole price, nothing held equal | +31.5% | +27.6% to +35.5% |
| Same floor area | +32.7% | +29.6% to +36.0% |
| + same property type | +19.8% | +17.3% to +22.4% |
| + same build period | +10.1% | +7.6% to +12.8% |
| + same year of sale | +3.8% | +1.8% to +6.0% |
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 SA11
| Sector | Sales | Raw gap | Like-for-like | 95% range |
|---|---|---|---|---|
| SA11 1 | 878 | +22% | +4.4% ▲ | +0.1% to +8.9% |
| SA11 2 | 1,369 | +38% | +7.2% ▲ | +3.2% to +11.4% |
| SA11 3 | 1,600 | +33% | +2.2% | −1.0% to +5.6% |
| SA11 4 | 516 | +19% | +5.1% | −1.4% to +12.0% |
| SA11 5 | 723 | +32% | −0.2% | −6.1% to +6.2% |
▲ 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 SA11
| EPC band (last certificate before sale) | Sales | Median £ per m² |
|---|---|---|
| A | 6 | too few |
| B | 198 | £2,372 |
| C | 1,101 | £1,630 |
| D | 2,560 | £1,343 |
| E | 980 | £1,178 |
| F | 202 | £1,000 |
| G | 39 | £878 |
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.