| Measure | Grant | Net cost | Saving / yr | Payback | Grade effect |
|---|---|---|---|---|---|
| Hot water cylinder insulation | — | £15 – £30 | £88 | 0.3 yrs | +4.8 pts |
| Cavity wall insulation | — | £500 – £1,500 | £77 | 12.9 yrs | +4.2 pts · reaches D |
| Low energy lighting | — | £125 | £5 | 27.6 yrs | +0.2 pts |
| Band A condensing boiler | — | £2,200 – £3,000 | £64 | 40.9 yrs | +3.5 pts |
| Solar photovoltaic panels | — | £3,500 – £5,500 | £96 | 47.0 yrs | +5.2 pts |
| Floor insulation | — | £4,000 – £6,000 | £103 | 48.4 yrs | +5.6 pts · reaches C |
| Solar water heating(optional, beyond C) | — | £4,000 – £6,000 | £80 | 50+ yrs | +4.4 pts |
Grants verified 20 August 2026. Costs are the register’s indicative ranges. 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 £433 a year — a 3.3% annual return on £13,248.
Restated at the fuel prices assumed in July 2026. This certificate, assessed in 2019, states £1,018 a year at the prices assumed then. Modelled costs, not a bill.
Sold prices
Estimated today: £1,005,948 HPI-indexed estimate, not a valuation
Clarks Lane: 4 sales since 1995
Schools nearby
The schools’ own performance — Progress 8 shows value added, not just raw results.
| School | Phase | Distance | Progress |
|---|---|---|---|
| Tatsfield Primary School | Primary | 0.8 mi | — |
| Churchill Church of England Voluntary Controlled Primary School | Primary | 1.4 mi | — |
| Biggin Hill Primary School | Primary | 2.1 mi | — |
| Charles Darwin School | Secondary | 2.2 mi | Progress 8 -0.34 · below average (2023/24) |
| Oxted School | Secondary | 2.5 mi | Progress 8 -0.27 · below average (2023/24) |
| Meridian High School | Secondary | 4.0 mi | Progress 8 -0.70 · well below 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 E01032571, to 2026-06. An LSOA holds about 1,500 people, so this covers far more than one street.