1 Cosham Park Avenue, Portsmouth, PO6 3BG

1 Cosham Park Avenue is a four-bedroom detached house in Portsmouth (PO6 3BG). It has a recorded floor area of 51 m² (around 549 sq ft), construction records dating it to 1930-1949 and council tax band E. At 51 m² this is the smallest unit on EPC record across the building (51–138 m²). The building's EPC ratings span G to C, with this unit at the bottom. On EPC score it ranks last in the building (6 versus a best of 71). Other recorded features include a conservatory. The latest certificate (September 2015) shows a G (score 6), near the bottom of the EPC scale. Earlier certificates rated it E (May 2014); the latest reading is 2 bands lower. Between certificates, window efficiency went from Average to Good; while wall efficiency dropped from Good to Poor and hot-water efficiency dropped from Good to Very Poor. Main heating runs on electricity. The latest certificate is from September 2015, so improvements made since then won't be reflected.

At 51 m² it sits well below the postcode median (99 m² across 8 EPCs), making it one of the more compact homes locally. On energy efficiency it sits in the bottom 10% of properties in this postcode — significant headroom for improvement. Across 1999–2021, sale prices on this property compounded at 4.4% per year. Today's modelled estimate of £412,000 is 26.2% above the 2021 sale price. On a £-per-square-foot basis, the last sale (£595/sq ft) was about 133.9% above the typical sold price in the postcode. Sold May 2021 for £326,500. That sale was during the post-pandemic price surge, when transactions cleared materially above pre-2020 trend. One historical planning record sits against the property in 2022.