EPC rating and sold prices in SO14 (Southampton)
In postcode district SO14 (Southampton), homes rated EPC C or better sold for 16% more per square metre than D–G homes (median £3,133 vs £2,700, 3,540 sales). Like for like — same size, type, build period and year — the difference is +1.1% (95% range −1.1% to +3.3%): 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 66 m² against 79 m² for D–G; the most common build period is 2012 onwards for C+ and 1900–1929 for D–G; 2% of C+ and 10% of D–G sales are detached or semi-detached houses.
| Comparing C+ with D–G homes… | Difference | 95% range |
|---|---|---|
| Raw gap per m² (medians) | +16% | — |
| Whole price, nothing held equal | +1.9% | −0.9% to +4.8% |
| Same floor area | +11.9% | +9.8% to +14.1% |
| + same property type | +12.3% | +9.9% to +14.8% |
| + same build period | +1.4% | −0.9% to +3.7% |
| + same year of sale | +1.1% | −1.1% to +3.3% |
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 SO14
| Sector | Sales | Raw gap | Like-for-like | 95% range |
|---|---|---|---|---|
| SO14 0 | 514 | +54% | +11.3% ▲ | +5.8% to +17.1% |
| SO14 1 | 108 | +11% | too few | — |
| SO14 2 | 214 | +8% | +0.4% | −5.7% to +6.9% |
| SO14 3 | 1,603 | +8% | +0.4% | −2.8% to +3.7% |
| SO14 5 | 357 | +56% | too few | — |
| SO14 6 | 604 | +3% | +2.8% | −0.4% to +6.0% |
| SO14 7 | 140 | −8% | too few | — |
▲ 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 SO14
| EPC band (last certificate before sale) | Sales | Median £ per m² |
|---|---|---|
| B | 1,064 | £3,316 |
| C | 1,274 | £2,923 |
| D | 899 | £2,750 |
| E | 239 | £2,566 |
| F | 48 | £2,163 |
| G | 16 | £2,012 |
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.