120 St John Street, Islington, London, EC1V 4JS

120 St John Street is a mid-terrace house in Islington, London, London (EC1V 4JS). It has a recorded floor area of 27 m² (around 291 sq ft) and construction records dating it to 2007 onwards. At 27 m² this is the 2nd smallest of 5 units on EPC record in the building, where floor areas span 25–91 m². The building's EPC ratings span D to C, with this unit at the top. On EPC score it ranks first in the building (74 versus a worst of 55). The latest certificate (October 2013) shows a C (score 74). Earlier certificates rated it B (October 2013); the latest reading is one band lower. Between certificates, wall efficiency went from Good to Very Good, hot-water efficiency went from Very Poor to Average and main heating went from Very Poor to Poor. Main heating runs on electricity. The latest certificate is from October 2013, so improvements made since then won't be reflected.

Across 2007–2025, sale prices on this property compounded at 4.5% per year. Today's modelled estimate of £922,000 is 73.7% below the 2025 sale of £3,500,000, a rare downward gap that often correlates with deferred maintenance or unfinished works. At 27 m² the property is well over the postcode median (16 m² across 22 EPCs), placing it in the larger end of the local stock. A recent sale: £3,500,000 in May 2025. 11 planning records sit against the property, 6 approved, 2 refused. Past consents include an extension and HMO conversion, meaningful when judging how the property has evolved. The record references conservation-area consent, which constrain future alterations.