100 Sirius House, Falcon Drive, Cardiff, CF10 4RB

100 Sirius House is a semi-detached house in Cardiff (CF10 4RB). It has a recorded floor area of 100 m² (around 1076 sq ft), construction records dating it to 1996-2002 and council tax band F. At 100 m² this is the 45th smallest of 47 units on EPC record in the building, where floor areas span 39–116 m². The building's EPC ratings span E to B, with this unit at the bottom. On EPC score it ranks last in the building (52 versus a best of 86). The latest certificate (October 2018) shows an E (score 52), well below the UK norm with real room to improve. Earlier certificates rated it D (October 2008); the latest reading is one band lower. Between certificates, lighting went from Average to Good; while roof efficiency dropped from Good to Average and window efficiency dropped from Good to Average. Main heating runs on electricity.

At 100 m² the property is well over the postcode median (62 m² across 46 EPCs), placing it in the larger end of the local stock. On energy efficiency it sits in the bottom 10% of properties in this postcode — significant headroom for improvement. Today's modelled estimate of £200,000 is 37% above the 2022 sale price. On a £-per-square-foot basis, the last sale (£136/sq ft) was about 37.1% below the postcode norm. Last sale on file: £146,000 in July 2022. That sale was during the post-pandemic price surge, when transactions cleared materially above pre-2020 trend.