Flat 1, 23 Denning Road, London, NW3 1ST

Flat 1 is a two-bedroom semi-detached house in London (NW3 1ST). It has a recorded floor area of 57 m² (around 614 sq ft), construction records dating it to before 1900 and council tax band E. At 57 m² this is the largest unit on EPC record across the building (55–57 m²). The building's EPC ratings span D to C, with this unit at the bottom. On EPC score it ranks last in the building (67 versus a best of 74). The latest certificate (May 2020) shows a D (score 67), on the cusp of jumping into the C band. Earlier certificates rated it C (June 2010); the latest reading is one band lower. Between certificates, wall efficiency went from Very Poor to Poor and lighting went from Very Poor to Poor; while hot-water efficiency dropped from Very Good to Good and main heating dropped from Very Good to Good. The recommended improvements would push it to C (score 79).

Held since September 2000 — that's 26 years off the open market, well above the local norm. Across 1997–2000, sale prices on this property compounded at 12.7% per year. Today's modelled estimate of £755,000 sits 164.9% above the 2000 sale of £285,000. On a £-per-square-foot basis, the last sale (£465/sq ft) was about 42.2% below the postcode norm. At 57 m² it's 18.6% smaller than the typical home in the postcode (70 m² median across 59 EPCs).