25a, St Mary Street, Monmouth, NP25 3DB

25a is a three-bedroom semi-detached house in Monmouth (NP25 3DB). It has a recorded floor area of 107 m² (around 1152 sq ft), construction records dating it to before 1900 and council tax band E. It is a listed building, which means external alterations are tightly controlled but it may qualify for heritage tax reliefs. The latest certificate (June 2025) shows an E (score 53), well below the UK norm with real room to improve. Earlier certificates rated it D (August 2013); the latest reading is one band lower. Between certificates, roof efficiency dropped from Poor to Very Poor and window efficiency dropped from Poor to Very Poor. The recommended improvements would lift it to B (score 82), a 3-band jump.

At 107 m² the property is well over the postcode median (76 m² across 28 EPCs), placing it in the larger end of the local stock. It lags the bulk of the postcode on energy efficiency (less efficient than 75% of similar EPCs). 2 planning records sit against the property, 2 approved, 0 refused. The record references listed-building consent, which constrain future alterations. Across 1995–2017, sale prices on this property compounded at 6.3% per year. Today's modelled estimate of £341,000 is 26.3% above the 2017 sale price. On a £-per-square-foot basis, the last sale (£234/sq ft) was about 27.4% above the typical sold price in the postcode. Last sold in June 2017, so it's been off the market for around 9 years.