12a, Windsor Road, Cosham, Portsmouth, PO6 2TG

12a is a semi-detached house in Cosham, Portsmouth, Portsmouth (PO6 2TG). It has a recorded floor area of 63 m² (around 678 sq ft) and construction records dating it to 1900-1929. The latest certificate (February 2018) shows a D (score 64), on the cusp of jumping into the C band. When first surveyed in February 2010 the rating was E, the property has climbed 1 band since. Between certificates, wall efficiency went from Very Poor to Poor and lighting went from Average to Very Good. The recommended improvements would push it to C (score 74). At 63 m² this is the 2nd smallest of 47 units on EPC record in the building, where floor areas span 61–175 m². The building's EPC ratings span G to C across 47 units on file.

Across 1997–2014, sale prices on this property compounded at 4.5% per year. Today's modelled estimate of £148,000 sits 97.3% above the 2014 sale of £75,000. On a £-per-square-foot basis, the last sale (£111/sq ft) was about 32.6% below the postcode norm. Last sold in January 2014, so it's been off the market for around 13 years. At 63 m² it's 27.6% smaller than the typical home in the postcode (87 m² median across 46 EPCs).