1 John Street, Mountain Ash CF45 4HL

End-Terrace house · Built 1900-1929 · 77 m² · Owner-Occupied · Boiler and radiators, mains gas

Upgrade Plan

EB for £24,125 · £8,042 a gradeGet upgrade quotes
MeasureGrantNet costSaving / yrPaybackGrade effect
Loft insulation£100 – £350£1142.0 yrs+3.5 pts · reaches D
Heating controls£350 – £450£874.6 yrs+2.7 pts
Solar photovoltaic panels£3,500 – £5,500£22220.3 yrs+6.8 pts
Floor insulation£4,000 – £6,000£24020.9 yrs+7.4 pts · reaches C
Solar water heating£4,000 – £6,000£18626.9 yrs+5.7 pts
Solid wall insulation£4,000 – £14,000£25934.7 yrs+8.0 pts · reaches B

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

£2,141
per year at grade E
£1,033
per year at grade B

The full plan saves £1,108 a year — a 4.6% annual return on £24,125.

Restated at the fuel prices assumed in July 2026. This certificate, assessed in 2023, states £2,665 a year at the prices assumed then. Modelled costs, not a bill.

Sold prices

21 August 2018£85,000
17 May 2002£35,000

Estimated today: £138,093 HPI-indexed estimate, not a valuation

John Street: 8 sales since 1995

Schools nearby

The DfE register covers England. Welsh schools are held in a separate Welsh Government register, which we have not ingested yet.

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.

5.5
crimes a month
44
in the last 12 months
Violence and sexual offences
most common · 39% of the total

Police.uk street-level data for LSOA W01001204, to 2026-06. An LSOA holds about 1,500 people, so this covers far more than one street.

Energy data © Crown copyright, EPB Register© HM Land Registry, OGL v3We grade homes, never neighbourhoods.