311a, High Road Leytonstone, London, E11 4JT

311a is a mid-terrace house in London (E11 4JT). It has a recorded floor area of 62 m² (around 667 sq ft), construction records dating it to 1900-1929 and council tax band B. The latest certificate (March 2018) shows an E (score 42), well below the UK norm with real room to improve. When first surveyed in December 2013 the rating was F, the property has climbed 1 band since. Between certificates, wall efficiency went from Very Poor to Poor and roof efficiency went from Very Poor to Poor; while hot-water efficiency dropped from Average to Poor. The recommended improvements would lift it to C (score 71), a 2-band jump. Main heating runs on electricity. At 62 m² this is the 12th smallest of 13 units on EPC record in the building, where floor areas span 29–77 m². The building's EPC ratings span E to C, with this unit at the bottom.

At 62 m² the property is well over the postcode median (47 m² across 53 EPCs), placing it in the larger end of the local stock. It lags the bulk of the postcode on energy efficiency (less efficient than 83% of similar EPCs).