| Measure | Grant | Net cost | Saving / yr | Payback | Grade effect |
|---|---|---|---|---|---|
| Loft insulation | — | £225typical | £5 | 41.6 yrs | +0.4 pts |
| Low energy lighting | — | £20 – £45typical | £0 | 50+ yrs | +0.0 pts |
| Wind turbine | — | £2,750typical | £9 | 50+ yrs | +0.7 pts |
| Solar water heating | — | £5,000typical | £9 | 50+ yrs | +0.7 pts |
| Solar photovoltaic panels | — | £4,500 – £9,000typical | £11 | 50+ yrs | +0.8 pts |
| Solid wall insulation | — | £9,000typical | £12 | 50+ yrs | +1.0 pts · reaches D |
| Double glazing(optional, beyond D) | — | £1,200 – £4,900typical | £4 | 50+ yrs | +0.3 pts |
Grants verified 20 August 2026. Costs are the register’s indicative ranges, except where marked typical, which this certificate did not price and which are taken instead from comparable homes of the same type. Savings are restated at the fuel prices assumed in July 2026. Points per measure are estimated from 19.9 million certificates and rescaled to this home’s own certificate delta; the total is the register’s figure.
Running costs
The full plan saves £47 a year — a 0.2% annual return on £23,758.
Energy costs as modelled on the certificate, not a bill. This fuel has too few recent certificates to restate at today's prices.
Sold prices
Estimated today: £363,833 HPI-indexed estimate, not a valuation
Chalk Row Cottages: 2 sales since 1995
Schools nearby
The schools’ own performance — Progress 8 shows value added, not just raw results.
| School | Phase | Distance | Progress |
|---|---|---|---|
| Chelsfield Primary School | Primary | 0.5 mi | — |
| The Highway Primary School | Primary | 1.1 mi | — |
| Orion Blenheim | Primary | 1.5 mi | — |
| Harris Academy Orpington | Secondary | 1.6 mi | Progress 8 +0.15 · average (2023/24) |
| St Olave's and St Saviour's Grammar School | Secondary | 1.6 mi | Progress 8 +1.27 · well above average (2023/24) |
| Newstead Wood School | Secondary | 2.7 mi | Progress 8 +1.05 · well above average (2023/24) |
Schools from the DfE register, performance from the KS4 performance tables. Progress 8 is a GCSE measure, so primaries have none. Distance is straight-line from the postcode, not a catchment: admission is decided by the school, not by us.
Area context
Police-recorded crime for the wider neighbourhood, not this address. We grade homes, never neighbourhoods — so this is reported as a count, not a rating.
Police.uk street-level data for LSOA E01000680, to 2026-06. An LSOA holds about 1,500 people, so this covers far more than one street.