21 Treport Street, London SW18 2BW

Mid-Terrace flat · Built 1930-1949 · 47 m² · Owner-occupied · Boiler and radiators, mains gas

Upgrade Plan

DC for £100 · £100 a gradeGet upgrade quotes
MeasureGrantNet costSaving / yrPaybackGrade effect
Draughtproofing£80 – £120£711.4 yrs+2.8 pts · reaches C
Floor insulation(optional, beyond C)£800 – £1,200£8511.8 yrs+3.3 pts
Solid wall insulation(optional, beyond C)£4,000 – £14,000£9150+ yrs+3.6 pts
Double glazing(optional, beyond C)£3,300 – £6,500£3150+ yrs+1.2 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

£792
per year at grade D
£514
per year at grade C

The full plan saves £71 a year — a 71.0% annual return on £100.

Restated at the fuel prices assumed in July 2026. This certificate, assessed in 2014, states £549 a year at the prices assumed then. Modelled costs, not a bill.

Sold prices

15 December 2023£450,000
12 November 2015£390,000
10 March 2011£250,000
1 October 2002£180,000
16 October 1998£94,700

Estimated today: £413,137 HPI-indexed estimate, not a valuation

Treport Street: 227 sales since 1995 · £495,644 average over 10 years

Schools nearby

The schools’ own performance — Progress 8 shows value added, not just raw results.

SchoolPhaseDistanceProgress
Swaffield SchoolPrimary0.1 mi
Floreat Wandsworth Primary SchoolPrimary0.2 mi
Allfarthing Primary SchoolPrimary0.3 mi
Southfields AcademySecondary0.5 miProgress 8 +0.48 · above average (2023/24)
Saint Cecilia's Church of England SchoolSecondary0.9 miProgress 8 +0.35 · above average (2023/24)
Burntwood SchoolSecondary0.9 miProgress 8 +0.34 · 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.

23.9
crimes a month
263
in the last 12 months
Anti-social behaviour
most common · 27% of the total

Police.uk street-level data for LSOA E01004494, to 2026-06. An LSOA holds about 1,500 people, so this covers far more than one street.

Treport Street

How this home sits against its street.

81
graded homes
65.7
average score
D
most common grade
+1.3
this home vs street
Energy data © Crown copyright, EPB Register© HM Land Registry, OGL v3We grade homes, never neighbourhoods.