21 Blackweir Terrace, Cardiff, CF10 3EQ
About 21 Blackweir Terrace
21 Blackweir Terrace is a mid-terrace house in Cardiff (CF10 3EQ). It has a recorded floor area of 96 m² (around 1033 sq ft), construction records dating it to 1900-1929 and council tax band D. The latest certificate (June 2024) shows a C (score 71). When first surveyed in October 2013 the rating was E, the property has climbed 2 bands since. Between certificates, wall efficiency went from Very Poor to Poor and window efficiency went from Very Poor to Average. The recommended improvements would push it to B (score 82).
3 planning records sit against the property, 2 approved, 1 refused. Past consents include an extension, meaningful when judging how the property has evolved. At 96 m² it's 20% larger than the typical home in the postcode (80 m² median across 34 EPCs). Across 1999–2015, sale prices on this property compounded at 10.3% per year. Today's modelled estimate of £338,000 is 25.2% above the 2015 sale price. On a £-per-square-foot basis, the last sale (£261/sq ft) was about 83.3% above the typical sold price in the postcode. On the market in January 2015 and unlisted since — roughly 11 years.
Everything you need to know about 21 Blackweir Terrace
The true value, the hidden risks and the full sale history, in one report.
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Energy performance
EPC Rating
Property Improvements
Changes detected from historical EPC data
Heating controls changed
Single glazing replaced with double or better glazing
Loft insulation installed or upgraded to 250mm+
Heating controls upgraded for better temperature management
Wall insulation improved
Get a survey for this property
Level 3 Building Survey
Because the property was built before 1919 and has solid (non-cavity) walls, we believe a Level 3 building survey should be considered.
From £955 · Includes VAT
Planning history
3 applications on record at 21 Blackweir Terrace, Cardiff, CF10 3EQ
- Apr 2014ExtensionOutlineOutcome in report
Extension: Rear of property
LAWFUL DEVELOPMENT CERTIFICATE IN RESPECT TO A SINGLE STOREY REAR EXTENSION, REAR DORMER ROOF EXTENSION AND THE CONVERSION OF THE ROOFSPACE INTO LIVING ACCOMMODATION.
- Documents
- 12 docs on file
- Reference
- 14/00604/DCH
- More recent applications — locked
- ExtensionMay 2019Decision
- FullMay 2019Decision
Unlock 21 Blackweir Terrace, Cardiff, CF10 3EQ's full planning history
You're seeing the shape of it. The report has the substance.
- Every decision — granted, refused or withdrawn (3 on record)
- All 3 applications on this property in full, plus 6 notable nearby
- The 34 documents, officer reports & conditions
- What the pattern means for extending or converting here
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Sales history & valuation
21 Blackweir Terrace has more than quadrupled in price since its earliest registered sale in 1999.
£338,000
Modelled from EPC, postcode comparables and a sale-price growth of 10.3% per year over 15 years.
£270,000
Growth on file: 10.3% per year over 15 years.
Sales timeline
26 January 2015Most recent
£270,000
+126.0%over 10 months20 March 2014
£119,450
+99.1%over 14 years13 September 1999
£60,000
Median price across the last 5 sales in CF10 3EQ: £314,000 (2024–2022).
Nearby sales in CF10 3EQ
33 Blackweir Terrace, Cardiff, CF10 3EQ
Sold Apr 2024
£360,00045 Blackweir Terrace, Cardiff, CF10 3EQ
Sold Feb 2023
£290,00015 Blackweir Terrace, Cardiff, CF10 3EQ
Sold Oct 2022
£445,00041 Blackweir Terrace, Cardiff, CF10 3EQ
Sold May 2022
£230,55257 Blackweir Terrace, Cardiff, CF10 3EQ
Sold Jan 2022
£314,000
Versus other Blackweir Terrace homes
EPC Rating for 21 Blackweir Terrace runs comfortably ahead of the street norm.
Price per m²
£2,813
Street avg £2,177
Floor Area
96 m²
Street avg 89 m²
Habitable Rooms
6 rooms
Street avg 5 rooms
CO₂ Emissions
3.0 t/year
Street avg 3.7 t/year
Everything you need to know about 21 Blackweir Terrace
The true value, the hidden risks and the full sale history, in one report.
Pick your report · every report is £14.99
One time fee only - money back guarantee

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The neighbourhood at a glance
Reported crime in the wider district is trending notably upward year-on-year.
Crime
10/mo
Rising year-on-year across the wider district.
Nearest stop
0.1 km
Blackweir — bus stop.
Go deeper on the local area
A Local Area report breaks down crime, transport links, schools and air quality in depth.






