21 Duffryn Avenue, Cardiff, CF23 6LE
About 21 Duffryn Avenue
21 Duffryn Avenue is a semi-detached house in Cardiff (CF23 6LE). It has a recorded floor area of 150 m² (around 1615 sq ft), construction records dating it to 1967-1975 and council tax band F. The latest certificate (June 2026) shows a C (score 75), near the top of the C band. This certificate was lodged in the last six months, so the rating reflects current condition.
Held since October 1997 — that's 29 years off the open market, well above the local norm. Only one transfer is on record with HM Land Registry, suggesting it has stayed in the same hands for a long time. At 150 m² the property is well over the postcode median (106 m² across 7 EPCs), placing it in the larger end of the local stock. Its energy rating outperforms most of the postcode (better than 86% of similar EPCs). Today's modelled estimate of £616,000 sits 486.7% above the 1997 sale of £105,000. On a £-per-square-foot basis, the last sale (£65/sq ft) was about 77.9% below the postcode norm.
Everything you need to know about 21 Duffryn Avenue
The true value, the hidden risks and the full sale history, in one report.
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The data behind every report
Energy performance
The EPC has just been inspected, so the rating reflects current condition.
EPC Rating
Certificate validity
Valid until 1 June 2036
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Planning history
21 Duffryn Avenue has no planning applications on record.
But the area is active
1 notable application nearby — larger schemes and conversions that could reshape the street. The report maps them all.
Sales history & valuation
21 Duffryn Avenue's modelled value sits at over four times its earliest registered sale price (1997).
£616,000
Modelled from EPC, postcode comparables.
£105,000
Recorded with HM Land Registry.
Sales timeline
12 October 1997Most recent
£105,000
Median price across the last 5 sales in CF23 6LE: £440,000 (2023–2017).
Nearby sales in CF23 6LE
Versus other Duffryn Avenue homes
On price per m², 21 Duffryn Avenue runs well behind the street norm.
Price per m²
£700
Street avg £3,341
Floor Area
150 m²
Street avg 139 m²
Habitable Rooms
8 rooms
Street avg 6 rooms
CO₂ Emissions
3.5 t/year
Street avg 5.9 t/year
Everything you need to know about 21 Duffryn Avenue
The true value, the hidden risks and the full sale history, in one report.
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One time fee only - money back guarantee
The data behind every report
Similar properties nearby
The neighbourhood at a glance
Rail-style transport is unusually close for this postcode.
Crime
169/mo
Falling year-on-year across the wider district.
Nearest stop
0.1 km
Duffryn Avenue — bus stop.
Go deeper on the local area
A Local Area report breaks down crime, transport links, schools and air quality in depth.