30 Lock Keepers Court, Blackweir Terrace, Cardiff, CF10 3EZ

30 Lock Keepers Court is a one-bedroom end-of-terrace house in Cardiff (CF10 3EZ). It has a recorded floor area of 37 m² (around 398 sq ft), construction records dating it to 2007 onwards and council tax band C. At 37 m² this is the smallest unit on EPC record across the building (37–84 m²). The building's EPC ratings span D to B, with this unit at the top. The latest certificate (October 2018) returns a B (score 82), comfortably above the UK average. When first surveyed in November 2008 the rating was C, the property has climbed 1 band since. Between certificates, hot-water efficiency went from Poor to Average, lighting went from Very Poor to Very Good and main heating went from Poor to Average. Main heating runs on electricity.

At 37 m² it sits well below the postcode median (68 m² across 35 EPCs), making it one of the more compact homes locally. Its energy rating outperforms most of the postcode (better than 80% of similar EPCs). Across 2004–2023, sale prices on this property compounded at 0.8% per year. On a £-per-square-foot basis, the last sale (£292/sq ft) was about 47% above the typical sold price in the postcode. Sold January 2023 for £116,250.