12 High Street, Irthlingborough, Wellingborough, NN9 5TN

12 High Street is a semi-detached house in Irthlingborough, Wellingborough, Wellingborough (NN9 5TN). It has a recorded floor area of 35 m² (around 377 sq ft) and construction records dating it to 2003-2006. At 35 m² this is the smallest unit on EPC record across the building (35–187 m²). The building's EPC ratings span F to C, with this unit at the top. The latest certificate (November 2018) shows a C (score 71). The rating has held steady at C across 2 certificates since August 2015. Between certificates, lighting went from Very Poor to Poor; while wall efficiency dropped from Very Good to Good and window efficiency dropped from Good to Average.

Untraded for 30 years, with the last transfer in July 1996. Only one transfer is on record with HM Land Registry, suggesting it has stayed in the same hands for a long time. Today's modelled estimate of £171,000 sits 116.5% above the 1996 sale of £79,000. On a £-per-square-foot basis, the last sale (£210/sq ft) was about 96.1% above the typical sold price in the postcode. At 35 m² it sits well below the postcode median (78 m² across 17 EPCs), making it one of the more compact homes locally. Its energy rating outperforms most of the postcode (better than 82% of similar EPCs). One historical planning record sits against the property in 2014.