20 Blackbirds Way, St Mellons, Cardiff, CF3 5RE

20 Blackbirds Way is a three-bedroom semi-detached house in St. Mellons, Cardiff, Cardiff (CF3 5RE). It has a recorded floor area of 89 m² (around 958 sq ft), construction records dating it to 1967-1975 and council tax band D. The latest certificate (November 2013) shows a D (score 56), a step below the typical UK home. The rating has held steady at D across 2 certificates since December 2008. Between certificates, lighting went from Very Poor to Very Good; while wall efficiency dropped from Average to Poor and roof efficiency dropped from Average to Poor. The recommended improvements would lift it to B (score 86), a 2-band jump. The latest certificate is from November 2013, so improvements made since then won't be reflected.

Held since July 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. On energy efficiency it sits in the bottom 10% of properties in this postcode — significant headroom for improvement. Today's modelled estimate of £227,000 sits 298.2% above the 1997 sale of £57,000. On a £-per-square-foot basis, the last sale (£59/sq ft) was about 24.5% below the postcode norm.