EPC rating and sold prices in NW9 (Barnet)
In postcode district NW9 (Barnet), homes rated EPC C or better sold for 8% more per square metre than D–G homes (median £6,209 vs £5,745, 7,534 sales). Like for like — same size, type, build period and year — homes rated C or better sold for 2.4% less (95% range −4.3% to −0.5%). 2 of 7 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 70 m² against 85 m² for D–G; the most common build period is 2012 onwards for C+ and 1930–1949 for D–G; 3% of C+ and 42% of D–G sales are detached or semi-detached houses.
| Comparing C+ with D–G homes… | Difference | 95% range |
|---|---|---|
| Raw gap per m² (medians) | +8% | — |
| Whole price, nothing held equal | −10.3% | −11.9% to −8.6% |
| Same floor area | +3.7% | +2.5% to +5.0% |
| + same property type | +11.2% | +9.4% to +13.0% |
| + same build period | −1.4% | −3.3% to +0.6% |
| + same year of sale | −2.4% | −4.3% to −0.5% |
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 NW9
| Sector | Sales | Raw gap | Like-for-like | 95% range |
|---|---|---|---|---|
| NW9 0 | 1,236 | +9% | +3.1% | −1.3% to +7.7% |
| NW9 4 | 2,033 | −5% | −10.5% ▼ | −14.6% to −6.1% |
| NW9 5 | 1,634 | +2% | −3.9% ▼ | −7.5% to −0.2% |
| NW9 6 | 441 | −7% | +4.4% | −1.4% to +10.5% |
| NW9 7 | 944 | +7% | +3.0% | −1.2% to +7.4% |
| NW9 8 | 566 | −4% | −3.7% | −9.0% to +1.8% |
| NW9 9 | 680 | −1% | −1.6% | −6.3% to +3.3% |
▲ 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 NW9
| EPC band (last certificate before sale) | Sales | Median £ per m² |
|---|---|---|
| A | 5 | too few |
| B | 3,570 | £6,132 |
| C | 1,691 | £6,406 |
| D | 1,675 | £5,773 |
| E | 486 | £5,724 |
| F | 79 | £5,556 |
| G | 28 | £5,339 |
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.