138a, Cambridge Street, Aylesbury, HP20 1BB

138a is an end-of-terrace house in Aylesbury (HP20 1BB). It has a recorded floor area of 34 m² (around 366 sq ft), construction records dating it to 1900-1929 and council tax band A. At 34 m² this is the smallest unit on EPC record across the building (34–160 m²). The building's EPC ratings span F to C across 23 units on file. The latest certificate (October 2020) shows an E (score 50), well below the UK norm with real room to improve. Earlier certificates rated it D (April 2009); the latest reading is one band lower. Between certificates, lighting went from Good to Very Good; while roof efficiency dropped from Good to Very Poor and window efficiency dropped from Good to Average. The recommended improvements would push it to D (score 56).

Untraded for 21 years, with the last transfer in February 2006. At 34 m² it sits well below the postcode median (73 m² across 22 EPCs), making it one of the more compact homes locally. It lags the bulk of the postcode on energy efficiency (less efficient than 82% of similar EPCs). Today's modelled estimate of £250,000 is 22.5% above the 2006 sale price. On a £-per-square-foot basis, the last sale (£557/sq ft) was about 206.7% above the typical sold price in the postcode.